just quits for no apparent Reason (Page 4/4)
Lou6t4gto APR 12, 06:40 PM
well now that I've REPLACED the Inj, MAP, IAC, Ign coil pickup, Wires,.... it does seem like it just could be that (THE COVERTER LOCKING UP MOMENTARILY) I did replace the switch about 4 years ago). only once though, did it die, restart and when I put it in gear it took of like a stick shift with the clutch engaged (cough , sputter, then smoothed out after the revs went up to about 1200. Well, Today I disconected the battery, cleaned every connection and ground on the car. checked out the ECM (seems someone replaced it with a "Reman" before I got it about 7 years ago). so now the codes are gone, so I'll see what happens next time I try to use it ! LOL.
IF it does it again, I will surely pull the lockup plug and see. Thanks
Fierogtfan88 APR 23, 02:18 PM
I am having the same problem with my 1988 Fiero GT with a 3.4 DOHC engine conversion. It ran fine for the first 1000 miles and now when I come to a stop light or am sitting at idle, sometimes it will just die. I will turn the key off and go to restart it and it will restart each and every time. Sometimes it will run for 5 minutes at idle and then die and other times it will idle for 30 minutes and die and other times it will keep idling until I am bored and shut it off myself. Since my car is now different than a stock 2.8, I am not sure where to look. I now have 3 coils for this car and they have been replaced as well as the ICM they are mounted on. I have a new fuel pump and sending unit and a new TPS. One thing I have not done as of yet is drive the car around for 20 minutes in town to reset the TPS. Not sure if I need to do that or not. One other thing I know I need to do is put a ground wire from the decklid hinge to the engine, just like the car had with the 2.8 engine. Any chance missing this ground could be my problem?
Lou6t4gto SEP 05, 12:12 AM
definitely Not the ground from the deck lid. mine, when it dies, the volts are still at 12 or better (No loss of current) fuel pressure also does Not drop when it dies !
vette7584 SEP 05, 09:54 AM
i had one that would do something very similar, it wound up being the fuel pump relay, replaced it and the stalling stopped.
Yorgle SEP 05, 10:19 AM
Years back I had a 77 Cobra II and it would mysteriously die whenever I came to a quick stop. As with your car, she would always start right back up without any issue. I spent many months replacing parts and adjusting things until I realized that the big bundle of keys on my keychain was swinging forward and momentarily bumping the ignition switch to OFF.
Lou6t4gto SEP 05, 06:16 PM
MAYBE Progress. Getting Closer. finally 'EVIDENCE . changed out the ign switch, made no difference that I could tell, drove the car around the block a couple of times, AC on or off. no problem, shut off and restarted and let it idle, AC on/ off, nothing. according to the volt gauge, there is 12 volts or better at ALL times. Then I hooked up my Fuel Pressure gauge. (runs at 10psi). idles for a couple of minutes at 10 psi (good idle), then the pressure starts to drop !!! reaches 0 and it quits ! but shut it off,& restart, and it starts and runs just fine with 10 psi again ! The PUMP, Lines, and filter are all Brand new, also the relay.
**** "What is it" that is supposed to get the relay to "keep the Fuel Pressure up at 10psi" when it's Running ????
Dennis LaGrua SEP 05, 06:23 PM
Lou. it sounds like the fuel pressure regulator or fuel pump relay is bad.

------------------
" 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 "

[This message has been edited by Dennis LaGrua (edited 09-05-2019).]

Lou6t4gto SEP 05, 06:55 PM
BOTH are NEW... How to "test" them ???
Rexgirl SEP 05, 07:41 PM
Then possibly there is a bad connection at the wiring connector (on the firewall) to the fuel pump, or the FP relay connector? Or a break in the pump wires themselves at a stress location?