Pontiac Fiero

1988 Pontiac Fiero Fuel System Stalling Happens always When warm 

My 88 Fiero GT with 2.8 V6 (32k) stalls when I put it in gear. In park, it runs great. Strong acceleration and no other symptoms. No error codes. I have replaced the IAC, O2 Sensor, MAP, checked the TCC, EGR, PCV, cleaned the throttle body. I can't figure out what else could be causing problem.

How did you check the TCC? I'm guessing it to be the cause since your engine runs great in Park.

Roger

I pulled the connector. I was told this was the way to test if the TCC was bad. Car continued to stall with connector removed.

Thats an easy trick if the clutch is having trouble releasing occassionally after a short drive. You don't want to allow it to apply. Fine if the clutch is not applied when you unplug the control solenoid. The clutch never sees the command to apply.

But, your clutch is STUCK in the apply position and the defective control valve won't let the fluid vent to release the clutch. When you drop the car in gear the engine stalls because the tranny is in the highest ratio gear. To shift into the lowest gear (1st) it has to come out of the highest. Unplugging a stuck solenoid won't unstick it.

Make sense?

Roger

I suggest you check out the cost of replacing the TCC Solenoid. It should fix you up.

1988 Pontiac Fiero Engine Hesitating When driving When warm 

Hi,

I have just recently had a problem with my 88 Pontiac GT (2.8 V6).

I have had a number of parts replaced over the last six months (catalytic converter, ignition coil, plugs and wires, alternator, compressor, oxygen sensor, EGR valve, TCC solenoid). All were replaced as part of maintenance or to fix a specific problem. All seemed to do their job - car was running great.

Since the last service, a problem has developed where the tach gage shows a blip in running speed and it feels like the car hesitates slightly. this seems to happen after driving 20 to 30 minutes and is brought on quicker running freeway speeds. Once the speed flicker starts it continues until the car is shut off. when let sit to cool, car starts and seems OK for another 20 to 30 minutes.

This last time, I was able to park the car, put it in neutral and change the throttle setting from the engine bay while watching the dash tach. I could replicate the tach flicker and from standing over the engine, it sounded like the engine may be backfiring.

I have check the ignition and a dealership looked at it and said it needed a new coil, EGR valve and a battery change... neither changed the problem. The did an electrical system check and found only the battery bad

Any thoughts?

Any smoke from the exhaust-- when you rev the engine while the problem is present?

Inspect the plugs to see if they show signs of a rich conditon (black plugs) or lean (clean/almost blistery white appearance).

Hi,

No smoke that is noticable during the condition.

Plugs were changes within the last 500 miles. I looked at them yesterday and they look OK, nothing unusual. The car has not been driven very much due to the issue.

The condition is intermitent, and once it starts, I don't drive it much beyond that point. I have been trying to diagnose for the last month or so.

Thanks

How long after the tune-up did it take this problem to occur? This engine can be very fussy about spark plug wires, many aftermarket wire are inadequate right out of the box.

The car ran great for about a 1000 miles... then on a trip to work (freeway commute of 60 miles) it started the intermittent hesitation/stall just as I arrived at the gate. I got the car home, but the condition repeated its self after about 25 miles of driving.

The spark plug wires (and all accessories) are AC Delco

Douglass,

Any additional feedback??

This time of the year, it is possible to get water in the gas.Tough to diagnose,Adding gas line antifreeze (methyl alchol) to the gas.I usually buy mine at the hardware store, $10 gallon which is better than the $3.99 4 oz bottle at gas station. Just do not use more than 10% MIXTURE (10 gallons gas 1 gallon alchohol)
There are also some good injector cleaner fuel additives on the market.
I would not be happy if the dealer did that to me!

I am doubtful... The car has exhibited the intermmitent problem since the summer. Has had many tanks of gas and fuel injector cleaner.

The problem arises under pretty repeatable circumstances... run 20 to 30 minutes and accelerate the car. It sound like a mini backfire.

Your thoughts on distributor timing?

The distributer timing should not change or have those symptoms,If you have acess to a volt ohm meter test the wires to and in the dist., while wiggling the wires.Check the vacuum advance, if dist has one, I cannot remember how many I have changed! Many! It would not hurt to check the egr valve, not only if it is opening and closing properly but that it does not have any carbon buildup under it.

Checked and replaced the EGR valve... no difference made

Mechanics used to do, as a regular part of the maintenance, do a compression test, when changing the plugs.If the comp. is uneven, you will never get a smooth running engine.The comp test will also show a slighty burnt valve, which might give a slight popping or backfiring sound.If you notice a low cylinder, do a wet test on it.

1986 Pontiac Fiero Ignition System   

my son drove the car yesterday,when he went out to start the car all he got was a clicking sound, when i got home from work i tried jumping the battery, nothing not even the clicking, i removed the battery and had it checked it was bad i installed a new battery and still nothing car will not start. The car was outside in the cold all night.

Hi,
When a Fiero will not start, nor make a sound, there are 3 possible faults.

#1 Weak or dead Battery. (You took care of this one)

#2 Bad cables, wires or connections

#3 Bad starter.

A simple test. Turn on the headlights. Watch to see if they dim when trying to start the car.

If the lights do not come on, you have either a bad battery or bad wiring/connctions. If the lights come on, but dim when trying to start, you have a weak battery, or bad starter. If the lights do not dim when trying to start, you have a bad starter, or starter wiring.

I would say about 95% chance you need a starter.

Sterlingfixer