Posted by ChuckRock on June 21, 2010

I will be adding items here to outline my plan for my project. I hope to be updating this soon and a lot.

My Fiero Project Plan!
Started:	6/21/2010
Brainstorm Area				Notes:
	Body
		Paint
				I am going to keep the stock Red and Silver, but add textured semi-gloss black to all the vents.
		Front
			Fenders
				One Idea I had is to be able to get more rubber on the road was to increase the length of the “A” arms. I’ve found a few places around that sell kits and or parts to do that for Lambo kit cats. I’m not going there, but I would like to have a wider stance that would also improve cornering. So to keep in legal I will need to get wide body fenders and to make them have that extra something I would add vents on the back of the fender by the front of the doors.
			Headlights
				I have most all the parts I need just need to get busy and put them all together. I am going to do the headlight mod so they only need to come up about half way and change the type of light bulb that is used.
			Driving Lights
				I want to redesign the parking/driving lights to not be one in the same. I had an idea to use LEDs to make while or blue driving lights that would be place in the same place as the current Parking/Driving lights and still have the parking lights using more LEDs. The driving lights would turn on when ever the car was placed in drive when the ignition was in the on position. You would be able to over ride that with a light switch on the dash.
			Hood
				Add vents to the hood to help stop air build up under the hood.
		Rear
			Fenders
				Same goes for the back fenders as for the front. The difference is that the vents would be on the front side with duct work to point the in coming air in to the engine compartment. I am looking at adding 3″ to each side for just the “A” arms and then add another inch or so for fatter tires. It’s about 6″ to 10″ added width to the car. Also I would be adding some scoops to the where the current tinted panels are now. Not sure where I saw them, but I know some one was selling these that were also a tinted Plexiglas.
			Tail Lights
				All the Tail Light including the center stop light changed out for LEDs. But I want if I can to keep the stock Pontiac tail lights.
		Right
				Gonna make it simple here Lambo doors, LED marker lights
		Left
				Gonna make it simple here Lambo doors, LED marker lights
		Top
				If I can find everything I need to do the conversion, I am going to change it from a sunroof top to a T-top. I would go to a Targa top but then I would have to do work to the under carriage to strengthen it. But before I do this I will complete the engine, tranny and drive train mods. That way I can see what kind of body torque problems I may have with a larger HP motor.
	Front Trunk
				Right now the battery has been moved up here under the old spare tire. I think I want to add a small fuel cell up here, so on long trip if I am not close to a gas station I have a reserve. I have recently ran it out of gas at only a little over 150 miles. I hope to see better mileage when I get a new tranny and engine. But I would still like to know if I run out of gas I have a reserve just in case. I am going to remove the old spare tire. it will not do any good when I add the brake mod to the car and I am running 17″ wheels now any way. Because this area has a good seal and even after driving for a year I can open it and there is hardy any dust or dirt in there. I am planning to add an on board computer, in addition to the ECM. I will get more in to that in the interior section.
	Rear Trunk			As of now I am not doing anything here just making sure it does not leak.
	Chassis
		Brakes
			Front
				This is simple Corvette brake mod
			Rear
				This is simple Corvette brake mod
		Suspension
			Front
				As mentioned before I am going wider. SO I will do it the correct way and get new 3 inch wider “A” arms. I will also be replacing the front sway bar with a little fatter one. Of coarse I will need to put some good shock. No I am not lowering it!
			Rear
				As mentioned before I am going wider. So I will do it the correct way and get new 3 inch wider “A” arms. I will be taking the sway bar from the front and adding one back here as well. I may have to lower the back about an inch. As of now the rear of the car is higher than the front by about an inch. Before I do that I’ll wait and see how it looks with the new suspension. It may take care of it self.
	Engine
				I have decided on a 4.3L V6. I can get the horse power that I want out it and still have some room in the engine compartment. Plus I can use V8Archies V8 kits to do the car justice.
		Mods
				I will build the 4.3 to put out around 300 to 350 HP without being supercharge or turbo’ed. I think that’s respectable out put for a 2600+/- pound car. As I find out more details as to what I can do to it I will update The Plan and Budget.
	Transmission
				I know I want to stay with a automatic, but I am not sure yet if I will use a 4T60HD or the 4T65HDe. I want to add paddle shifters and setup torque lock to be engaged depending on if I am using the paddles to shift or letting the ECM do the shifting.

Posted under My Project

Posted by ChuckRock on June 1, 2009

In this article I’ll cover the general things that apply to all Fiero versions, then later I’ll break out the version specific and detail items.
Contrary to popular belief, vacuum plumbing problems are a major issue. Even small vacuum leaks can cause major headaches.

A major problem? Why?

The ECM will try to compensate for leaks up to a certain size. The leak will often cause performance problems without setting DTCs in the ECM. Depending on exactly where the leak is, it can unbalance the entire engine.
Let’s say you’ve got an Iron Duke and the EGR is leaking slightly around the base. This allows air to enter the intake right near the middle cylinders, leaning them out just a little. The ECM tries to make up for this by increasing the fuel feed. The end result is that the end cylinders are probably running rich. The car may seem to run pretty normally but you’ll take a hit in fuel economy and most likely you’ll have strange drivability problems that are often hard to duplicate.
Any vacuum leak is letting air in after the IAC and Throttle Plate. The ECM tries to make up for this by closing the IAC and likely increasing the fuel flow. This can cause a number of odd things to happen, like goofy Idle and hesitation. Ultimately, there is no such thing as an acceptable vacuum leak. All leaks must be found and fixed.

Tools:

Spray can of “throttle body” and Fuel Injection cleaner. (This is safe for all EFI. Carburetor cleaners can sometimes do damage to EFI parts. Don’t use it.) ((I do NOT recommend most people use the propane search method. It is far to easy to start a fire with this method, especially if done with improvised equipment.))
Assorted line plugs and port caps.
Hand operated vacuum pump such as “Mighty Vac” or equivalent. If you are buying one of these, just get the whole vacuum brake bleeding kit. Then you’ll get more use from it and bleed the brakes or clutch allot faster.

General:

Eliminate the nonessential items first. Start the car after each of the following and see if it has solved your problem.
Disconnect the 2 lines to the Fuel Vapor Recovery canister. Plug the ports on the throttle body and/or manifold.
Disconnect the Cruise Control line and plug its manifold port.
Disconnect the EGR line from the throttle body and cap its port. (I’ll get more into the EGR later)
In the front compartment disconnect and plug the line on the brake booster. DO NOT attempt to drive the car with the booster disabled! The brake booster can leak internally. Carefully inspect the booster vacuum line and all it’s clamps. All joints in this line should be clamped and the rubber hose sections free of cracks or other damage. Make sure there are no rusted sections of steel line. (The section inside the cabin is likely OK.) If any section of the line looks questionable spray the suspect area with EFI cleaner. Check the line to the MAP sensor carefully. Hard line doesn’t like being bent, especially when cold. (DO NOT spray the MAP sensor with solvent when searching for a vacuum leak!)
If the above have not solved the problem then carefully begin searching with the spray cleaner. Start the car and spray the throttle body mountings and work your way around whatever isn’t disconnected. DO NOT spray the distributor, coil(s), sensors or IAC with cleaners or solvents! You will likely damage them or start a fire. Use as little spray as possible to find the leak.
Don’t soak things. Test an area, let it dry then test another. The RPMs should change one way or the other when you spray the leak.

Fuel Vapor Recovery Canister:

This device catches vapor from the fuel tank. It uses 2 vacuum lines. The large (purge) line is connected to manifold vacuum. This line is used to ventilate the canister. The smaller (control) line is connected to the main bore of the throttle body and only opens the purge valve beyond a certain amount of throttle.
Problems with the canister can include failure of the purge valve to close and cracks in the purge valve body or canister itself.
There is also a fiber filter in the bottom of the canister that should be replaced periodically.
Another problem that this device can develop is flooding. Flooding is caused when liquid fuel is forced up the vent line into the canister. A flooded canister can cause rich mix problems with the engine. A canister that has been flooded should be replaced. To prevent flooding avoid “topping off” the fuel tank when you fill up. If the nozzle of a retail fuel pump is defective, and they often are, then you can pressurize the fuel tank and force fuel up the vent line into the vapor canister. It doesn’t take allot of liquid fuel to screw up the canister. Even if the pump doesn’t force fuel into the canister, fuel expansion in the tank can and often will. Either way, topping off the tank is a bad idea.

Quick test….

Disconnect both lines and connect a hand vacuum pump to the large line. Give the pump a squeeze and make sure the line holds vacuum. 10 inches is plenty of vacuum for this test.
Now use the pump on the small line. Draw only 3-4 inches maximum on this line! More than a few inches vacuum can damage it. While you have vacuum on the control line, blow into the purge line. Air should move freely. While blowing into the purge line release the vacuum on the control line. The valve should close and block all airflow in the purge line.

Cruise Control:

Leaks in the cruise control servo diaphragm cannot be fixed. Some people have had luck cleaning the valves on the servo and/or the dump valve. (The dump valve is a backup valve that kills the cruise when the brake is pressed and is mounted separately from cruise servo.)
There is also a vacuum reserve canister in the cruise system. Older style canisters are often metal and are prone to rusting out. Replace these with new style plastic canisters.
There are 2 styles of canister. The ones with 2 fittings usually have integral check valves. The ones with single ports are used with a check valve in the manifold line.
You can replace the can and inline check valve with a 2 port vacuum ball, but you must also insure that the plumbing is redone to work correctly. I think the larger port on these is usually the manifold side but test it to make sure. The exact size of the canister is not very critical. Any canister of approximately the same volume or greater will work. You can get good used plastic canisters for about nothing at any salvage yard. The plastic ones will last nearly forever. Just make sure the check valve is working before you leave the yard. (Blowing into one port is very easy. The other is not going to let you if the valve works.)
BTW: You can get these from many American made cars. It doesn’t have to be a GM product.

As you can see, changing to the vacuum ball also simplifies the vacuum lines quite a bit. If you make this change, and cruise stops working, then you may have put the lines on the Vac Ball wrong.

Brake booster:

The brake booster unit should not be disassembled. If you believe it leaks then it will need to be replaced. You generally can’t get parts for the booster and there is a very heavy spring inside it that likes to send thing flying.
The check valve that the vacuum line connects to can go bad. This usually manifests as brakes that work right only at idle. The check valve shell can crack and cause a vacuum leak. You can replace the valve by itself. Try MotorMite’s HELP! or VacuTite lines.
Don’t forget to check the brake filter on cars that have them. The plastic shell of them is pretty tough but it can crack or melt. The brake filter does need to be replaced on occasion. If it plugs up you will have brake problems.

Hard lines:

Hard vacuum line can be a pain to service. You can get the line but finding the correct fittings can be difficult at best. (The rubber fittings are reusable if they are in good condition and sealing tightly to both the line and the port.) If you replace hard line with soft line make sure the new lines are not pinched or collapsed from bending too tightly. The soft line should be sized to properly slide onto the fittings and stay tight. Don’t stretch undersized line to fit. It will likely split in short order.
New Hard Line can be shaped or straightened by careful use of heat. (Try dipping the line in very hot water.) Be careful not to pinch or stretch the softened line. Don’t try to form old lines. They usually break even when warmed.
Note: If you replace the MAP sensor line with soft line then keep the line as short as possible. The soft line will have a larger internal volume per inch of line than the hard line. This increased volume can affect the reaction time of the MAP sensor. A slow MAP sensor will likely hurt performance. Even when using hard line it is best to keep the MAP feed short as possible.
Make sure the steel PCV valve line is not rusted through anyplace and that both elbows are sealed. GM recommends clamps on the elbows. Be careful with the clamps that you don’t cut into the soft elbows.

4 Cylinder specific:

The 4 cylinder EGR is bolted directly to the intake manifold. Make sure it’s tight. The bolts have a nasty habit of coming loose. Replace the gasket if the bolts have come loose at all. (The FelPro EGR gasket costs about $1.00 at most parts stores.)
The EGR valve is hard to test for leakage. Make sure the valve isn’t binding.
One way to test EGR problems is to make a block off plate and seal the manifold openings. Then run without it for a little bit. Note: Permanently running the car without the EGR is a crime in the United States. Running the car without the EGR can cause detonation, which can damage the engine. This is a testing procedure only.

87-88 TBI:

Be careful not to spray the MAT sensor’s plastic parts with solvent. Depending on the solvent used, you can damage the sensor. The MAT sensor is located to the right of the TBI unit and is screwed into the intake manifold. Avoid intake backfires in these engines. If the car backfires into the intake, the MAT sensor should be inspected for damage. If the MAT sensor has been cooked it should be replaced. (The MAT sensor is used in calculating fuel/air ratio.) Don’t over tighten the MAT sensor or you may split the intake manifold.
Check the base of the TBI for leaking, especially if there is any evidence the air cleaner has hit the trunk wall. (Read the torque strut article.) There is a specific sequence to tighten the 700 TBI to the manifold. Read the TBI 700 article. The emissions vacuum line map for these years is in the TBI 700 article. That map doesn’t include cruise.

V6 specific:

You’ll need to check the EGR plumbing very carefully. Use extreme caution if you decide to use spray or gas searching on this. The V6 EGR plumbing gets hot enough to light off many solvents on contact.
The V6 EGR control valve must also work properly. If it’s acting up, try electronics parts cleaner. Don’t use the cleaners with lubricant in them. The lubricants will hold dirt and quickly clog the valve up again. (Most “Tuner wash” and contact cleaners have lubricants in them.)
To test this valve, with the engine off, blow into the line connected to the EGR valve. The air should exit the vent hole. Cap the vent hole and blow again into the EGR port. No air should come out the manifold port.
To test during run, connect a vacuum gauge to a T in the EGR valve line. You should be able to see the vacuum rise and fall when the ECM has activated the EGR valve. Using an ECM scanner with the vacuum gauge may be helpful. I think the ECM will tell you when it’s trying to open/shut the EGR. You should see a corresponding change on the gauge. (I think the ECM may also report the EGR vacuum sensor status. I can never remember just what ECM reports what.) You must also carefully inspect the entire plenum. If bolts have come loose you may be able to simply tighten them but likely you will need to replace the gaskets.
Rodney Dickman now offers formed metal vacuum lines for the V6.

Posted under Engines

Posted by ChuckRock on June 1, 2009

Warning! Don’t force anything into the ALDL connector! If you damage the connector then you can have problems when using ECM scanners and other tools that have the proper size terminals.

Note! It is possible that the ALDL may be installed with the Key up or down.
The above picture is Key Down. Use the key sticking off the ALDL by terminals C & D to determine which way the ALDL is positioned.
With the key down, when you are sitting in the drivers seat, Terminal A is on the bottom row on the passenger’s side. With the key up A is the top terminal closest you.
To read ECM codes short terminals A & B together and turn the key to run, codes will blink thru the Service Engine Soon light. (Don’t start the car!)
Terminal F is used for some tests of the Torque Converter Lockup System. See the TH125 article for more information.
Terminal G is the fuel pump test point. It will have 12V on it whenever the pump is on. It can also be used to feed 12V to the pump to determine if the pump or the controls are a problem.
None of the other terminals are used during normal service routines so leave them alone. If you short them out you could do major damage to the ECM. (Only a few terminals in the ALDL are even wired.)
You can find the complete pin out of this connector and others here –> Fiero Tech Zone He also has a brief ECM code list.
There is a cheap tool to read codes in the tool section of most parts stores. It is a simple stamped metal item and cost about $2. You can also use any wire that will make snug contact.
If you have an Autozone store near you ask the counter man for the book and key to read the codes. The book is titled “What Does It Mean When Your `Check Engine’ Light Comes On?” This small book lists common codes for GM Ford and Chrysler and how to test some of the ECM sensors. The book is free.
The best tool for dealing with the ECM is a scanner. These tools read the full data stream from the ECM and will report data from sensors and how the ECM is reacting to it. The AutoXray GM OBD-1 scanner is one of many tools available and cost about $150-200. Other scanners are available but most cost more.

Posted under Engines

Posted by ChuckRock on May 28, 2009

Who’s There?

Ping.
Ping Who?
Ping I just knocked a hole in your piston….

Engine Knock, Fuel Octane and other myths

Thing One: Never use higher Octane fuel than the engine needs to prevent knock.

I’m going to try to greatly simplify a very complex topic here. They write encyclopedias about this stuff. I’m going to try to keep it to a few pages.

What is Knock/Ping?

When the engine is running normally, the spark plug fires and the flame spreads evenly thru the cylinder. The mix burns evenly until consumed. When the engine Knocks or Pings it means the fuel was set off at the wrong time and/or the fuel was set off from multiple sources. Both conditions are bad for the motor and rob you of performance and fuel economy.

What causes it?

There are many things that can cause it. Most of them you can and should fix.
Here’s a list of common items. (In no particular order.)

• Over advanced ignition timing. (Very easy to do with mechanical distributors but still possible with electronic ignition.)
• Vacuum leaks or EGR problems. (These are way more common than people think.)
• Exhaust leaks. (Even small upstream leaks can screw up O2 sensor accuracy.)
• Wrong spark plugs or other bad ignition parts.
• Carbon buildup in cylinders. This alters engine compression and can create hot spots.
• Engine sensors dirty/bad or damaged sensor wiring. If a sensor is lying to the ECM the car will never run properly.
• Compression increased as a result of engine or head rebuild. (This can be intentional or a side effect.)

What is Fuel Octane Rating?

That number you see on the pump comes from a bunch of tests that determine how much the fuel helps resist engine knock. The higher the number the more it resists knock and it usually means the fuel is also less volatile. This last bit is the big rub… Less volatile fuel will often perform worse, not better as many people think. How much you may notice this depends on the specific engine in question. In any case, using more Octane than needed will not increase engine performance. Higher-octane fuel sells for more than regular fuel. Compared to most 87 Octane fuels, you pay 10-20 cents more per gallon for a product that costs them almost nothing more to make. That extra dollar or two per tank can add up really fast. Why spend it if you don’t have to… The carmakers all list the minimum Octane rating for fuels in the owner’s manuals. For most Fiero I’m pretty sure it’s 87 Octane. (I know the 87 owners manual lists 87 for both the 4 and 6 cylinder.) Oh, and the factory 2.8 has lower compression than the 4 cyl, so don’t go thinking bigger engine means more Octane. (2.8 is 8. something:1 while L4 is 9:1) Even motors with 100,000 miles or more can run the specified Octane if they are in good shape. Mine has over 150,000 miles and is running wonderfully on 87 Octane fuel. (Even WaWa fuel that is usually one of the lowest priced fuels around the region.) Note: Someone in the forums pointed out the European Octane ratings are higher than the U.S. numbers. Keep in mind other regions of the world use different methods and rules for grading fuel. While the European Octane number might be higher, that doesn’t mean they are automatically better than U.S. fuel at preventing knock.

Bending the rule, additives in Pump Fuel

All U.S. fuel is required by the EPA to have cleaning additives in it. Fuel meeting the minimum requirements is perfectly fine for most cars. Some fuel vendors promote their fuel based on the additive package. These additives won’t add power so much as restore or maintain it by removing carbon and dirt. These additives have contributed to confusion over octane ratings. These cleaning additives, which are unrelated to Octane rating, may help performance in some vehicles. This can be a function of brand, grade, or both. Some brands use the same additive package in all grades of fuel, while others put the “good stuff” only in higher grades. As an example, Texaco puts “Cleansystem3®” in all their fuel. Other brands may put their best additive package only in premium grades. What results you’ll get from any additive packages will depend greatly on the condition of your engine. None of them are likely to clean up a really dirty motor but they may help an engine expel minor carbon buildup and other dirt. Some no doubt do this better than others. Other than cost, it won’t hurt anything to shop fuels based on their additive package. If one product works better for you than something else that’s great. Otherwise don’t buy more than you need. To use Texaco again… Since they put Cleansystem3® in all grades, you’d still run the lowest Octane fuel the engine will take. If Texaco 87 Octane fuel works, their 89 and higher isn’t going to do anything but cost more. (Texaco is just a handy national brand for an example… I use a regional brand most of the time.)

The car knocks/pings…

We’re talking generally stock engines here. Even a regular rebuild should run on the OE octane or maybe one step higher. Obviously if you’ve done a big build up or super/turbo setup, you could need more octane. If a car that was built to run 87 Octane only runs on 90+, the engine may just be dirty or you could have mechanical problems. If the car knocks even on the highest Octane pump fuel you almost certainly have engine problems that need repair. These are some things I look for when an engine knocks. Triple check for vacuum leaks. Even a tiny leak can lean out a cylinder enough to cause knocking without tripping ECM errors. (You’d be surprised how easy it is to have a vacuum leak that only messes with one cylinder.) Check the cooling system very carefully. Knock/Ping can also be an early sign of overheating. Don’t assume the temperature gauge is correct. (Even if it is correct, don’t assume there are no cooling problems. A common problem here is a head gasket installed wrong. This can make some cylinders hot even if coolant temp reads ok on the gauge.) Check timing on distributor motors very carefully. The difference between knocking and not can be just a couple degrees of advance. (Defective or improperly configured Mechanical Distributors are great for this.) Use OE EGR valves (GM, AC Delco, Motorcraft, etc.) whenever possible. If you must use a “universal” style valve, make sure it’s a good brand. A crappy EGR valve can really screw up an engine. (I have seen aftermarket valves die in as little as a year.) Is the engine suffering carbon buildup? You might want to try one of the carbon removal processes. Carbon buildup can be the result of past fuel system problems and other things. It usually won’t go away without help. Is the engine sucking oil? This can both alter the octane of the mix inside the engine and cause carbon buildup. It’s probably time to rebuild some or all this engine or find another. Higher Octane fuel or carbon removal is at best a temporary fix. 87-88 Fiero L4 motors with DIS may need a different PROM in the ECM. GM had an update to tweak ignition timing a bit. (The new PROM numbers are in DIS notes. This kind of stuff is common with ECM/PCM controlled motors.) This should be considered ONLY AFTER all other mechanical items are checked out.

An example

Awhile back, my car started knocking under certain load conditions. (87SC L4 w/ DIS) I’d also lost some fuel economy. This went on for weeks and since the problem wasn’t consistent, it was really a pain to find. It did it even on 90+ Octane fuel. (Since it hadn’t done this previously, I didn’t think the PROM update would help.) In searching for a vacuum leak, I took off the EGR to see if maybe the middle of the gasket had partly blown out. (A common problem with this type of EGR setup.) The EGR wasn’t that old, and like many aftermarket units not easy to test. Since it wasn’t very old I didn’t really expect it to be bad but just out of habit I checked to see if the pintle was moving ok while it was off. It wasn’t moving at all… It turned out that the 2-year-old aftermarket EGR valve had failed totally. It had jammed in such a way as to not open and still leak slightly. (It never set any kind of code in the ECM during all this.) The spring in the top had actually broken and you could hear it rattling around when shaken. Replacing the EGR with a good used GM valve solved both the knock problem and cranked fuel economy back up to 26 mpg even in really crappy traffic. (The EGR gasket cost about a dollar.) The lesson, yet again, is never to assume recently installed parts are good.

Fuel additives

Octane Boosters and Cleaners

Octane boosting additives don’t help much except maybe for when you have a modified/race engine and can’t find suitable fuel at the pump. A stock vehicle that won’t run on pump gas has something wrong. Octane booster products, like higher Octane fuels, usually will not increase performance. How much, if anything, a cleaning product does will depend greatly on how messed up the engine is. Don’t expect any miracles from most of them. Even professional cleaning products may not remove heavy buildup. Some add in Octane boosters and cleaning products may actually damage the older styles of port fuel injectors used by GM and some others. In the older injectors, used thru the late 90’s, the solenoid coil is exposed to the fuel. (This helps cool the coil.) Most products are probably ok but make sure they are used as directed on the container. Mix them stronger than directed and they might eat your injectors. (The newer GM injectors are redesigned and do not expose the coil to the fuel just because of this problem.)

I’ve heard fuel changes by season….

Yes fuel does change by season and it also changes by city and region. This double whammy can make buying fuel quite confusing. If you suddenly drop or gain 2-4 MPG, you might be a victim of Reformulated or Oxygenated fuel. In some vehicles these fuels may also induce knock/ping that forces you to a higher, more expensive, grade of fuel. What many people call Winter Gas is defined as Oxygenated or Reformulated Gas (RFG) depending on where you live. They are supposed to reduce air pollution. These fuels contain MTBE and other chemicals to increase the oxygen content of the fuel. They cost more, often cause odd problems, bite performance, and you get less MPG. There is little you can do about the problems caused by RFG and Oxygenated fuels. On HEI engines, try retarding the timing very slightly if you have ping/knock.

Acceptable Alcohol Fuel Content

Methyl Tertiary-Butyl Ether
Fuel containing Methyl Tertiary-Butyl Ether (MTBE) may be used, providing there is no more than 15% alcohol by volume. MTBE is under investigation in many places. Some states are likely to ban it in future. MTBE is intended to reduce air pollution but has been shown to be a serious problem when it gets in the water. Small amounts of MTBE can pollute large amounts of water and the stuff is hard to filter from drinking water.

Ethanol
Fuel containing ethanol (ethyl) or grain alcohol may be used, providing there is no more than 10% ethanol alcohol by volume. Ethanol plays a roll in Octane rating and pollution control. Its presence in motor fuels is likely to increase greatly as MTBE (Methyl Tertiary Butyl Ether) is phased out in many regions. Higher concentrations of Ethanol will alter the fuel beyond what the ECM/PCM can deal with, and may be too strong for some fuel system parts to handle. Pre-computer engines may need considerable carburetor and distributor adjustments to run right.

Methanol
GM recommends against any methanol use. It can damage the fuel system parts. (Nearly all carmakers say stay away from methanol even now.) “Dry” gas typically contains Methanol but not enough to hurt anything. Fuel containing methanol (methyl) or wood alcohol may be used, providing there is no more than 5% methanol by volume. Use of fuel (gasohol) that contains more than 5% methanol can corrode metal fuel system components and damage plastic and rubber parts.

Posted under Engines

Posted by ChuckRock on April 7, 2009

Note: If you have 87-88 L4, you can use an ECM Scanner to test the MFL. The DIS ECM will report all the switches operation except the brake pedal switch for the dump valve. Besides checking switch condition, the scanner will tell you if anything else in the switch wiring is bad.

Multi Function Lever

The Multi Function Lever contains the switches that operate the Cruise Control system. Note that the MFL does not contain any other switches. The actual wiper, headlight beam select, and turn signal select switches are all inside or on the steering column.

The Cruise switches are pretty easy to test. Almost any Ohmmeter will work. C235, is about the easiest place to test at. This small connector is along the steering column. It’s easier to get at C235 if you drop the trim panel from under the steering column.

These tests will usually detect a dead switch in the lever but may not detect a switch with intermittent dropout! Work each test several times. The meter should always drop to the same point. Wiggle the lever while doing them as well. It may help you detect damage to the wiring.

Connect the meter across terminals A and B. Turn on the slide switch. The meter should drop to Zero. Now push the slide to Resume/Accel and release it. The meter should not move when you do that.

Now connect A and C. You should get Zero on the meter Only when you push the slide to R/A.

Finally, connect between A and D. with the slide in the On position, press the Set button. The meter should go to zero.

MFL switche, there’s not much to the thing. Unlike the HL Beam Select and the Wiper switch that are down in the column, these switches are inside the lever head. They aren’t the most rugged things on earth.

The switches are prone to both wear and dirt issues. Fortunately the same MFL is used in many GM models and are plentiful both new and used.

The MFL isn’t made so it can be repaired. A few people have managed to clean the switches when they acted up. In most cases you are just better off replacing the whole MFL. To make that easier, tie a string to C235 before you pull the wire out. Then use the string to pull the new wire down the column.
Those of you with access to an oscilloscope can use it to test the switches. You need the scope and a battery. A handy battery is to get a 9 volt “Transistor” battery and a clip from Radio Shack. The trace should jump and stay when you push the switch. If it bounces around as you hold the switch then the switch is shot. (Most volt and ohmmeters don’t have rapid enough response for this test but you can try it with them as well.)

Servo Notes

Some people have had luck cleaning the valves on the servo. It’s worth a shot. In most cases you need to replace the servo.

Vacuum Canister

Some people repair the metal one. Unless you need to do that for show reasons, just find an equivalent plastic vacuum ball. You can get them from almost any car made.

Servo Adjustment

Notice on the servo there is a plate with a bunch of holes. Use the hole that allows the servo to completely rest with a slight slack in the cable.

Dump Valve

There is a redundant dump valve in most cruise systems. This valve is mounted near the servo and is on an independent circuit operated by a switch on the brake pedal. (There are two brake switches for most cruise systems.) Don’t forget to check this valve and its wiring if the servo isn’t holding vacuum. To temporarily disable this valve, plug the large port on the servo.

You should NOT operate the car long term without this valve. The valve makes the servo dump quickly when the brake pedal is pushed. Without it servo release is greatly slowed.

Posted under Electrical

Posted by ChuckRock on October 15, 2008

ECM upgrade (1227730) for stock 2.8 Recently a friend of mine brought me his Fiero to have a swap done. He had a very high mileage stock 2.8 and 125-C and wanted me to swap in a lower mileage 2.8 and 440-T4 OD transmission. Not content with sticking with the stock 2.8 ECM, I convinced him to swap out ECMs during the swap as well. In short, it was an excellent choice! The ECM that was used in this swap was the 1227730 unit which was used in many 1987-92 era GM cars. For this application, I elected to use the $88 code mask programming which was designed to be used in a 1990-92 Camaro/Firebird 3.1. The Camaro/Firebird 3.1 is very similar to the stock Fiero 2.8 including it’s use of a distributor and iron-heads. With that being said, there were some significant differences between the two systems… The 7730 ECM running $88 code mask does NOT use or need the 7th injector (cold start). The 7730 ECM controls the coolant fan relay directly. The 7730 ECM will interface with stock Fiero 2.8 ECM wiring harness. (although some modifications will be needed) The 7730 ECM uses a knock sensor. The 7730 ECM interfaces directly with the speed sensor which means changes can be made in the programming to calibrate the speedo without having to change out the plastic gears on the VSS sensor itself. The 7730 ECM running the $88 code mask will NOT work with the stock Fiero 2.8 EGR valve. It is designed to work with the digital EGR valve used in the early-mid 90’s era GM V6 cars. I went ahead and designed an adapter plate and had another Fiero friend make one up so we could use the digital EGR valve on the stock Fiero 2.8 y-pipe. The biggest advantage to using the 7730 ECM in a Fiero application is not only more tunable options in the programming, but the drivability and response time of the engine improved significantly. Gone was the unstable idle characteristics of the stock 2.8 which some have said existed from the factory. Gone was the high idle flare upon startup. We quickly found out that using the 7730 ECM system on the stock 2.8 greatly improved it’s drivability as well as throttle response and performance characteristics. Believe it or not, using the newer computer, even this stock 2.8 ran and acted like a new engine found in today’s new cars! And because the 7th injector, fan switches, and vacuum-controlled EGR valve were no longer required, it also allowed us to clean up the wiring and vacuum lines on the stock 2.8 engine as well… I think this is one of the most worthwhile upgrades for a stock (or even modded) 2.8. Obviously, it can also be used on 3.1 and 3.4 OHV swaps. Although if you are swapping in a newer 3.1 or 3.4 that has provisions for the DIS ignition system, I would recommend using the DIS as well. The 7730 ECM will work with the DIS ignition system if you use a different code mask (programming).

Posted under Upgrades

Posted by ChuckRock on October 14, 2008

4.3L S10 to Fiero Engine Swap

Old Engine Removal

Sorry, I didn’t have my digital camera when I started actually tearing into the car. But never fear, I still have some pics to share of the end result.

The car was backed into the garage to start teardown. Mind you, this is an un-heated garage and I am starting the swap in mid-December in Wisconsin. Do I get a point for that? Anyways, teardown pretty much followed the Chilton manual I have…pretty much. This is how I did it, some steps may vary on your particular car and patience level.

1. Remove deck lid & side covers – makes for much easier access when changing plugs, too…

2. Remove Battery and disconnect ground straps.

3. Soak cradle bolts with PB Blaster.

4. Drain coolant into suitable drain pan. Keep away from animals.

5. Remove air cleaner.

6. Disconnect throttle cables. My cable was shot and being a bi$%h so I just cut it.

7. Remove heater hose at intake.

8. Disconnect vacuum hoses.

9. Soak cradle bolts with PB Blaster.

10. Disconnect fuel lines and pump relay.

11. Disconnect O2 sensor. Try not to smash it into the firewall when removing engine….

12. Disconnect trans cooler.

13. Disconnect engine to chassis ground strap(s). Don’t forget this stupid thing.

14. Disconnect engine wiring harness on the engine.

15. Disconnect A/C Lines. I didn’t have to discharge it because it didn’t work anyways.

16. Wheel cherry picker over and position to lift car and engine.

17. Break lug nuts loose so they can easily be removed with wheels off ground.

18. Soak cradle bolts with guess what? more PB Blaster. You’ll begin to love this stuff later.

19. Attach chain to engine block and lift car high enough to knock florescent light down.

20. Lower car, fix light, raise car, paying more attention this time.

21. Insert jack stands under jacking points on rear of car. Wheel wells must be at least 45″ high.

22. Lower car carefully on jack stands, be sure they are stable.

23. Remove wheels and calipers, I took my brakes off entirely.

24. My park brake cable was rusted solid, so I had to cut it off.

25. Remove strut bolts.

26. Loosen front cradle bolts, but don’t remove yet.

27. Raise cherry picker just enough to support engine.

28. Remove rear cradle bolts. I got super lucky and mine didn’t spin.

29. Remove bolts from front mounts, and lower cradle assembly onto heavy-duty creeper.

30. Wheel engine out of right hand wheel well.

31. Miller time.

Air tools are very very handy for the cradle bolts, especially if your car is having its engine yanked out for the first time in 23 years. Above all, be smart and DO NOT work under a car supported by only the cherry picker or jack. If the Fiero falls, you WILL be crushed, there isn’t enough ground clearance to get lucky.

Engine Bay Cleaning

First of all, every Fiero owner-turned-mechanic is obliged by unwritten law to provide the “standing in the engine bay” picture upon successful removal of the engine. Here is my compliance:

Ok, time to get serious. One of the problems I had with the car was a badly rotted battery tray. Most old Fieros are going to have this problem. I had a bungee holding the battery down on the tray, which worked fine for a while. In hindsight though, it was pretty stupid since the battery sat about 2″ away from the spinning water pump pulley and belt.

So one hard corner later, guess what? The strap gave out, the battery slid into the pulley and sprayed energized hydrochloric acid all over my car’s engine compartment. nice! So needless to say, I later cleaned it out, sprayed a little paint over the bare metal to attempt to stop the rusting, and tacked in a spare battery tray out of an old Chevy truck my brother had lying around. That worked great and I was able to bolt the battery in place. But I still had a rusty mess in the engine bay.

Fast forward to today. I jumped in the engine bay and started pulling down the nasty old insulation to get at the metal.

With the old firewall insulation out of the way, I could start cleaning the engine bay out for the 4.3L to go in. What good is a swap if the engine bay looks like trash? I ground down the spot welds and removed all the old rusty remnants of the factory battery box.

I then proceeded to scotch-brite and paint the engine bay. I ground some of the old brackets off the firewall since they will no longer be needed.

That pretty much concludes the engine bay cleaning portion of the build.

Why The 4.3L V6?

I seem to get asked that question alot, so here I will go into length on the research I did regarding this engine and my own experiences.

The biggest question I hear on PFF is, “why a 4.3 when you have to do the same work to install a V8? why not just go with a SBC and get the extra 2 cylinders?” Well, here’s why. The 4.3L is lighter than the 350 Chevy, and it fits in the Fiero engine bay much nicer without having to run a goofy water pump setup. The TBI wiring is a piece of cake, and personally, I want to have some extra room in the engine bay for future forced induction possibilities. Yes, I could get more power per $ with a SBC, but again, these are MY reasons, if you don’t agree, then put something else in your car.

You can compare the dimensions of the SBC and the 4.3L V6 below:

I originally planned on installing a 4.9L Cadillac engine, as the power was phenomenal off low end and it bolted right up to the fiero trans. However, the wiring on the ‘84 cars is complicated because of the issues with the C500 connector’s location, as well as being confusing overall splicing the two harnesses together if you don’t have experience with these engines.

I used to own a 1991 K1500 Chevy truck with a 4.3L engine in it. That truck was amazing, it was a full-size truck, long bed 4×4, and that little V6 with 300,000+ miles could still light the tires. Torque up the wazoo! So having plenty of experience working on that 4.3L, as well as having done a swap on that truck and dealing with the wiring of the ECM, I knew alot about how the engine would wire to the Fiero: piece of cake. You can run the 4.3L on an engine stand, just plug the harness into the ECM and give it +12v.

A brief comparison of the two engines, in their respective vehicles:

————————-

1995 GMC K1500 (year I am getting my 4.3 from)

- 4,300 cc 4.3L V6

- 4″ bore, 3.48″ stroke, 9.1 compression ratio

- Overhead valve and two valves per cylinder

- Unleaded fuel

- Fuel economy Mileage (City / Hwy) 14/19

- Throttle body injection fuel system

- Curb Weight 4517 Lbs

- Power: 160 HP @ 4,000 rpm (CPI/Vortec Heads: 190HP @ 4,400 RPM)

235 ftlb @ 2,400 rpm (CPI/Vortec Heads: 250FtLb @ 2,800 RPM)

Pro: shares many perf parts with SBC (heads, cams, intakes, turbo syclone/typhoon parts)

Con: requires adapter plate and flywheel mods

1995 Cadillac Deville

- 4,893 cc 4.9L V8

- 92 mm bore, 92 mm stroke, 9.5 compression ratio

- Overhead valve, two valves per cylinder

- Premium unleaded fuel

- Curb Weight 3756 Lbs

- Fuel economy Mileage (City / Hwy) 16/26

- Multi-point injection fuel system (PFI)

- Power: 200 HP @ 4,100 rpm

275 ftlb @ 3,000 rpm

Pro: bolts right up to fiero trans, or 4T60/E

Con: very few performance hop ups besides reground cam & porting

————————-

The ‘95 Silverado (K1500) has a curb weight of 4,517 lbs, nearly twice that of the Fiero’s 2790Lb. A common rule of thumb is that every ten pounds of weight reduction is like adding 1 additional horsepower, so by that rule the Fiero will scoot as if it had an extra 173HP along with the existing 160, and anyone knows a Fiero with 333HP is going to be pretty damn quick. But enough with the shade tree math, its just a guesstimate. Obviously the same math applied to the 4.9L results in a Fiero equivalent of a 97hp boost on top of the 4.9L’s 200hp, which has the little 4.3L ahead by 36hp. Either engine will provide a nice quick Fiero!

Fuel economy is hard to figure, but seeing as that the engine is only pushing about half the weight of the donor vehicle, I am expecting something like 20/30. When I get the swap done, tuned and road tested, I’ll post my actual MPG.

I know a few TBI mods I did on the old truck I had, as well as the available cams, intakes and Vortec heads that will really wake up this little 4.3L. The TBI engines get a bad rap because of the crappy flowing pre-Vortec heads. Hot Rod magazine did a buildup of a 4.3L with ported non-vortec heads and only squeaked 300HP out of it. (they later did a 500HP supercharger on that same engine, but that’s a different story…maybe stage 5? hehehe…) I drive in the low end of the powerband, using the torque. I am a stoplight drag, 0-60 kind of Fiero Enthusiast. My engines rarely see over 4500RPM, so these torkie engines are my ideal platform.

I plan on adding 4 bolt mains to the 4.3L when I tear it down to install the cam and fresh bearings in the lower end. When my old 4.3L in the K1500 started to go, it was a bad rod bearing, so I will be pulling the engine apart to install high-quality Clevite bearings, and have the 4-bolt caps installed and the block line-honed at the same time. Seeing as that some form of forced induction may or may not be in the future, I like to have enough beef in the low end to do it.

There are FAR more performance parts available for the 4.3L than there will ever be for the 4.9L Caddy – partially because the 4.3L is 3/4 of it’s big brother 350 SBC, partially because of the 4.3L’s brief stint in the Busch Series cars. GM Performance Parts makes some nice 18° heads, and I think I recall Brodix making something as well.

So to summarize, for me and my purposes with the car, this engine is the ideal engine. Your opinions may differ, but don’t flame me saying I should just go SBC…I explained why I’m not, just read.

Posted under 4.3L, Engines