Good Evening,

I have searched for months through these and other threads to find all the different solutions to the several symptoms I was having.

- I was stalling in traffic - I R&R the TCC and that stopped.
- My ICM did finally fail - I R&R that and the stalling continues now only after 1 - 1.5 hours of driving. ( I carry a second)
- I also removed and reinstalled the ICM heat paste to make sure I had enough
- Ignition COIL is now new - still stalled after an hour
- tightened all Alternator wires.
- Distributor is new with Magnet and Magnetic pickup. - still Stalled after an hour


Here is what else I have gone through:

Plugs; Wires; Cap Rotor; Added Dielectric to all connectors; R&R fuel Filter; when it stalls and doesn't start back up RPMs are increasing; No codes; The Check engine light works; removed the Gas cap after the stalls start no change in symptoms; When I turn the key on I hear the Fuel pump Relay not 100% sure I hear pump but it does run so I really think that it is working..

My thoughts is that the failure is tied to the heat soaking - it is now the only constant.

There is no Catalytic converter; has K&N Filter & Side scoop.

So here are the current symptoms:

After a hour of driving (teaching my son to drive over 1.5 hours in a parking lot in 48 degree outside temp); water Temp normal; Oil Pressure reading normal; after the first stall - when you rev the engine in neutral - No issue. When I Accelerate with the car in gear - the car starts to accelerate and huffs (stalls) Then catches and backfires once. At this point it becomes intermittent: Sometimes after the Huff it continues to run when I stop the acceleration - sometimes it stalls out and I have to cycle the key a couple time without starting it for it to start. Then if I baby it on acceleration I can drive it home but when I accelerate aggressively it huffs and stalls.

What I have not yet done:

Tested Fuel pressure (why would I if it is solid for 45 minutes then it starts acting up?)
Vacuum leaks (Why would it run solid and after heat soak start acting up?)
Cleaned/tightened all the ECM contacts grounds etc. (electrical has always been FM to me)


Are there any other ideas to help me doing the Fuel pump next?

Hopefully I have left enough information.

Thanks for all this forum has helped with so far. I love my second Fiero; Well my sons first Fiero.

Randy of Georgia.

[This message has been edited by MetalBlue85GT (edited 02-01-2014).]

Don't see anywhere that you said you replaced the coil. These symptoms sound a lot like the coil overheating.

Thank you NetCam - I did leave that out of the list ToDo. But that is a good thought and cheaper than the Fuel Pump. Next on order is the Coil. Then another training session to see if it acts up again.

[This message has been edited by MetalBlue85GT (edited 01-19-2014).]

Take a look at the pickup coil in the distributor. Run this test:

""When I Accelerate with the car in gear - the car starts to accelerate and huffs (stalls) Then catches and backfires once. At this point it becomes intermittent: Sometimes after the Huff it continues to run when I stop the acceleration - sometimes it stalls out and I have to cycle the key a couple time without starting it for it to start. Then if I baby it on acceleration I can drive it home but when I accelerate aggressively it huffs and stalls. ""


these symptoms also could be the fuel pump, reduced pressure and flow, enough to rev the engine in neutral but not enough under load.
possible low voltage to pump also

Thank you for the distributor diagram - I will put that on the list too.

Fuel pump is my last resort - I appreciate your knowledge.

- So for the fuel pump theory ~ it never has happened with in the first 45 minutes of driving, I mean the car is solid and sporty - only after long driving. (heat soak)
So I am having trouble rationalizing heat and fuel since heat soak or 1-1.5 hrs run time seems to be the key to getting it to stall.

Sounds like I have a plan though I will start on the Coil next and go for another training drive.

Thank you as always good advice.

Randy

[This message has been edited by MetalBlue85GT (edited 01-21-2014).]

Changed out the Coil - no Change in symptoms. I was successful in getting the car to repeat the stall after 1 hour of driving then letting it idle in my drive way for 15 minutes.

One new thing that made me think: The car was idling just fine then I plopped down in the seat and it hiccupped. when I revved the engine it stuttered then as the idle came down it stalled (this was with fan blower motor running; headlights on and Radio on). it wouldn't start right up so I took the load off of the electrical system and then it started; revved fine a couple times; when I put it in gear it stalled; started right back up then when in park I put the electrical load back on the car and revved it and it stalled again.

So now I have two thoughts: a short in wires and Fuel pressure.

Next step today is to check out all the wires per the diagram above (replace the magnetic pickup). I will also re-check the Charging system to the Battery for shorts.
- refresh the grounds to the ECM and verify the wires at the Oil Sending unit.

I will report the findings.

Another instance of that same symptoms: https://www.fiero.nl/forum/Forum2/HTML/122336.html with a seemingly fuel pump resolution.

You are new to the forum, so perhaps you missed this important thread:

https://www.fiero.nl/forum/Forum2/HTML/043240.html

Well I took the distributor out of the car in order to replace the magnetic pickup ( two wires that connect to the back to the Ignition Control Module under the distributor cap.) As I was taking apart the distributor there is Magnet that is screwed in between the outer ring and the magnetic pickup. Mine was in pieces; 12 pieces to be exact.

On the top view you can see three rusty screws when I took those off there is a magnet under the rusty ring. it was shattered.

Does anyone know where I can get a replacement black magnet? otherwise I will be purchasing a whole refurb distributor

TOP VIEW


If you look close at the ring you can see the black, broken magnet.
Reluctor

Thank you for the Ground Link I think I have cable lying around that I can do that with.

Still troubleshooting; If I buy a new Distributor and that fixes it; I will come back and let people know if it fixed my problem,

Randy

[This message has been edited by MetalBlue85GT (edited 01-29-2014).]

So I found that you cannot order the Magnet ring So I had to buy a new Distributor. I installed it last night and this morning was the time to test. Son and I went to do the learner permit thing in the parking lot.

Sadly the issue was still there after one hour of practice. So here is a Recap:

After an hour of driving at or near idle; the car stalls. I had lights and the fan blower on and it would not start. I turned all of that off and let it sit a minute; looked for any signs of why in the engine area and then started it up and when I turned all of the lights and power back on it stalled; I let it sit longer and it started and I was able to get it home.

Now that I am home I am going find a way to hot wire the fuel pump to see if it still stalls. Searching for the way to do that now:

I will add the ground a better ground wire to the engine and frame soon - trying one thing at a time.

I had a fuel pump that would run for a while then fail. I found Delco pumps to be the most reliable.

I also had an ECM fail with the same symptoms. I took the console and ECM cover off, ran AC on high and the problem would disappeared ended up replacing the ECM.

I would start with the pump. If its a six cylinder pin G on the ALCL connector ( beside the lighter plug behind the cover) is wired to the fuel pump. A test light or meter to ground will show if the pump has power. You could also feed power to the pump at that point.

Sounds like how my fuel pump acted before failing.

Thanks for the confidence you guys are proving my troubleshooting. Not that I am happy to do the tank but its that last thing.

Last night I pulled out the Battery and dremelled all the grounds. and I added the Block to Tray 4gauge. I see some of the same benefits others have - Faster Windows; brighter Dash lights; door locks are better. Didn't solve the Stall.

After an hour of driving again it stalls - I have it at running temp and in my driveway now so I am going to go put a Fluke meter to all of it to see what I am pushing.

Planning the Tank drop now... If I am dropping the tank I am refurbing the whole thing so here we go - I will keep this thread posted.

Before you drop the tank, try hooking up a gauge and watch the fuel pressure to see if that's really the problem. It should be about 42psi with key on, engine off. With engine started it will drop into the high 30s. It should fluctuate in relation to the manifold pressure. Side note: it should also hold pressure with the key turned off, otherwise you may have a leaking injector, but that's not causing it to stall.

Leave the gauge on while the car heats up. Once you reach the failure state, see if the fuel pressure is still behaving like it's supposed to.

If pressure is low, try pinching the return line. If that fixes it, then suspect the pressure regulator.
Also while pressure is low, try checking the fuel pump voltage as Terry suggested.
If those check out then drop the tank.

quote Originally posted by MetalBlue85GT: I mean the car is solid and sporty - only after long driving. (heat soak)

You suspect the problem is "heat soak", yet unless I've missed it, I see no mention made of the trunk blower operating.

If I were you, I'd ground the fan switch and have this fan blowing full-time on the alternator and coil/distributor... just to see if this eliminates or at least delays the stalling.

And make sure there's plenty of air coming out the end of the tubes.

[This message has been edited by Patrick (edited 02-03-2014).]

TO Armos
I hooked up a Fuel Pressure gauge to the Shrader valve - 40 PSI car was Cold. Bled down to 20 psi over about 20 minutes. car running the PSI was about the same close to 40. I will heat it up again soon and look at it to see if it is Fuel Pump issues. I am not convinced its fuel related and I will follow the Pinch, Fluke and Pressure checks this week or Saturday.


TO Patrick

hmmm What blower in the trunk? If this is a real requirement to be there in Summer or Winter then you may have just found my issue.

I do not think my car has either - ALT or Coil fan - no tubes etc...

nothing in the rear that looks like tubes or a blower.

That is very interesting. I did change the Coil and the symptoms stayed the same but if that is a common failure to all hot coils then this could be it.

well this will be interesting to find all of that equipment and put it back in.

quote Originally posted by MetalBlue85GT: TO Patrick hmmm What blower in the trunk? If this is a real requirement to be there in Summer or Winter then you may have just found my issue. I do not think my car has either - ALT or Coil fan - no tubes etc... nothing in the rear that looks like tubes or a blower.

All '85-'87 Fieros that came with V6 engines are supposed to have a blower (hidden away on the passenger side of the trunk) that blows cool air through two aluminum tubes onto the alternator and coil/distributor. This blower operates any time the rad fan operates. Pontiac didn't go through all the trouble and expense of installing this stuff for no reason.

Possibly Roger Garrison owned your Fiero previously. (Inside joke.)

I found the blower in the trunk. the relay was laying there not hooked up.

I am going to look for the ducting on the Alt - but I know it is not at the coil.

more to come when I can squeeze some time into it.

Randy.

quote Originally posted by MetalBlue85GT: I found duct that has a flange but no pipes connected.

This image taken from another thread shows what these pipes look like.

Note: The red pipes have simply been placed in the engine bay beside the connected (non-painted) functional pipes.

Yep those are not there.. I found the flanges they connect to.

Saturday I am going to get the car to stall again.

I have the test light; Fuel gauge; fluke meter ready.

I will also clean all the ECM grounds and start going down the list I down loaded from above just for fun so everything else can benefit from the added power since I added the extra ground cable to the chassis.

I had a similar problem with mine. Replaced the fuel pump and no problems after that. There is an o-ring/seal inside the older pumps that can swell due to exposure to the alcohol in todays gas. That will cause the pump to slow and eventually stop. Modern pumps have an alcohol resistant o-ring/seal.
No guarantee that this will fix you're issue though. It still could be something else. But that's where I would put my bet.

Fuel pump is now replaced = 42 + PSI - I have yet to start it and test for the stalling. I will post how things go after the hellish storms that are about to hit the ATL. :P

Thank you for all of your insight - it has been fun. If this doesn't fix it I will be looking for an 85 auto ECM. lol...

quote Originally posted by MetalBlue85GT: Fuel pump is now replaced

I'm a little surprised you did that.

Unless I missed it somewhere, I don't recall you stating that a fuel pressure test had indicated that the fuel pressure had indeed dropped prior to the engine stalling.

As you now know (if you didn't know previously), dropping the fuel tank to replace the fuel pump isn't a whole lot of fun. (I've replaced fuel pumps several times myself.) I just hope you haven't done it for nothing.

I forgot to add what I found, after having all the test equipment on it. I drove it around until I hit about and hour with the blower working with no tubes to direct it. So I let it idle for a little longer driving around the neighborhood and parking then it finally started stalling. Everytime it stalled the first thing to go out of the test light on the ALDL, the ALT Volts and the Fuel Pressure was the fuel pressure dropped to twenty psi and stuttered. until it finally died.

I tested it about 5 times all the exact same pump pressure failed first and was erratic until it failed.

I guess we will see.

quote Originally posted by MetalBlue85GT: ...the fuel pressure dropped to twenty psi and stuttered. until it finally died. I tested it about 5 times all the exact same pump pressure failed first and was erratic until it failed.

Interesting.

This may seem obvious, but did you always have plenty of gas in the tank? (You know you can't trust the gas gauge, right?)

[This message has been edited by Patrick (edited 02-11-2014).]

Test drive complete I did I got 2 solid hours total the first hour and a half at 35 or lower (just like the test runs previously) then I took it on a trip up the Hwy for 15 miles and back. no hiccups or anything.

I am a happy Fiero driver. Now on to the rest of the quirks. the rest isn't drivability; heat, cruise control and making it look prettier.

Thanks for all the experienced advice.

Randy

Glad to read your problem is fixed. What did you do to fix it beyond the fuel pump?

[This message has been edited by Gall757 (edited 02-14-2014).]

I believe at this point it was all fuel pump all along. But in the beginning I think it had 2 other very similar and confusing symptoms.

- It would stall in traffic as I had to slow down - that ended up being the TCC solenoid. after I disconnected the wire that stalling stopped so I R&Rd the TCC solenoid.

- Then randomly I think the ignition control module ICM failed.

- Then I thought it was fixed and the constant stalling started any time at about an hour of operation ended up being the fuel pump, but I changed out everything in the ignition system to include the distributor. But it was the fuel pump all along.

It is solid now as far as the stalling goes.

I am off now to see why the TCC keeps engaging and disengaging at constant speed. I feel it lightly at 40mph but it is a lot more noticeable at 65mph. When I push lightly and hold the break it quits. so I know it has to do with the TCC.

quote Originally posted by MetalBlue85GT: I am off now to see why the TCC keeps engaging and disengaging at constant speed. I feel it lightly at 40mph but it is a lot more noticeable at 65mph. When I push lightly and hold the break it quits. so I know it has to do with the TCC.

Do you know the age of the transmission fluid? Bad fluid in an auto can cause shaking when the torque converter is locked. This was a common problem on some Fords. It's hard to get it all out, unfortunately.
I had an issue like this on my Fiero, where it feels like the lockup has trouble engaging, like it turns off and on and jerks the car noticeably. It was so bad at first that for a while I unplugged the lockup TCC. I thought for sure it was the solenoid, not the fluid, but after I did a couple fluid changes the problem was greatly diminished. It still does it sometimes but not nearly as bad.

I have only had the car since last March. I have recently changed the TCC Sole. so I know some of the fluid is good but I hear ya and I am going to just do the filter and get as much Fluid out I can.

The Level checked good.

Fluid and Filter has been changed. It was noticeably less at freeway speeds and the more I drove it the less I noticed it. Looks like I will wait a while and use my Pela Pump to suck out a whole bunch again.

That was a mess - now I know why I like to pay people to do that on my newer cars.

quote Originally posted by MetalBlue85GT: Fluid and Filter has been changed. It was noticeably less at freeway speeds and the more I drove it the less I noticed it. Looks like I will wait a while and use my Pela Pump to suck out a whole bunch again. That was a mess - now I know why I like to pay people to do that on my newer cars.

Yeah, it's ridiculous that there's no drain plug. I guess they're worried about slow leaks not being noticed, but from what I hear Japanese transmissions have a drain plug. I could be wrong, I've never owned one myself.
They took it even further in the wrong direction with newer transmissions, where they don't even have a dipstick anymore. I guess they decided the average new-car buyer never reads it anyway, or reads it improperly.