Hello all, I’m back again with another Fiero issue. The engine on my1987 Fiero GT keeps quitting on me. I’ll be at idle at a stoplight and the engine will just stop. It starts up right away but then after 10 or 15 minutes it’ll just stop again. It keeps doing this.
I checked a bunch of stuff and everything seems to work properly. So I figure it’s the ECM, but not certain.
Has anyone had this issue with a GT and was the issue diagnosed? I hate to go out and buy a used ECM unless I know for sure. And if that’s what it is, is it just simply a switch out?
Distributor pickup coil, fuel pump or maybe the ICM?
Check the coil: see if corrosion in the windings? Fuel pump: can you hear it running? Running eratically? ICM as the last thing once all the others eliminated.
I would be supprised that the ECM is dead? You wouldn't have anything running at all.
------------------ "Turbo Slug" - '87 Fiero GT. 3800 turbo. - The fastest Fiero in France! @turboslugfiero https://youtu.be/hUzOAeyWLfM
[This message has been edited by Frenchrafe (edited 10-24-2025).]
Thanks guys. Not the fuel pump. If the coil was bad, it would not restart. I’ll check the ignition switch. I’ll run some tests on the ECM. Thanks again.
Thanks guys. Not the fuel pump. If the coil was bad, it would not restart. I’ll check the ignition switch. I’ll run some tests on the ECM. Thanks again.
How does it behave AS it's shutting off? Does it stumble and quit, such as... do the rpms slowly drop and then it just dies? That would make me think a failing IAC.
If your GT has an automatic transmission, and it dies when you come up to the stop, you should look at the Torque Converter Lockup Solenoid. It's easy to check if this is the problem, just unhook the square electrical plug on the firewall side of the transmission and see if the problem goes away.
How does it behave AS it's shutting off? Does it stumble and quit, such as... do the rpms slowly drop and then it just dies? That would make me think a failing IAC.
Simply shuts off. No stumble, etc. IAC is new not fuel related. I will take a look at the ICM in the distributor. Beats me.
[This message has been edited by Gene1000 (edited 10-25-2025).]
If your GT has an automatic transmission, and it dies when you come up to the stop, you should look at the Torque Converter Lockup Solenoid. It's easy to check if this is the problem, just unhook the square electrical plug on the firewall side of the transmission and see if the problem goes away.
Thanks. Not an automatic. I’ll look at the ICM in the distributor.
Crankshaft sensor? It could cause the engine to stop.
It might... if the 2.8 had one.
My experience with a failing ICM, is that the engine usually runs poorly for a short while before dying. Sounds more to me like a bad electrical connection somewhere which is suddenly cutting off power.
Patrick, I thought the 2.8L engine has a crankshaft sensor, but I could be wrong. IF it does, again IF, maybe that could be the problem. I’ll try the ICM and see what happens. Thanks all.
I hope I don’t jinx myself, but I replaced the ICM and it’s been running fine ever since. So far, it hasn’t shut down at all. Hopefully it’s fixed. Hopefully.
I hope I don’t jinx myself, but I replaced the ICM and it’s been running fine ever since. So far, it hasn’t shut down at all. Hopefully it’s fixed. Hopefully.
I rate the #1 problem of engine malfunction on the 2.8L to the ignition module. Even installed with a coat of thermal grease the AC Delco module brand was the only one that lasted in that hot location. There are now probably 20 brands of Chinese modules being sold today . If your ICM lasts please pass on the brand name.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I rate the #1 problem of engine malfunction on the 2.8L to the ignition module. Even installed with a coat of thermal grease the AC Delco module brand was the only one that lasted in that hot location. There are now probably 20 brands of Chinese modules being sold today . If your ICM lasts please pass on the brand name.
delphi. 1 has outlasted 3 2.8l engines now (~50k miles.....really bad luck) i have also used the cheapest duralast part (grey color) and had that last awhile. if you wanna go gm genuine parts use them from a 91 onwards s10 4.3 v6 they tend to get baked less and not fail in the s10s or the fieros in my experience so far using a used stash on club members cars
