88 IROC Intermittent starting problems
#1
88 IROC Intermittent starting problems
First time doing this so be kind! I have a 1988 IROC 305 TPI, 5 speed.
The past two months it's been driving be crazy. Intermittent starting. It will go a couple of days and then it will not start. And when I say wont start I mean the will turn over but it wont fire. Let it sit and come back, hours to a day, and it starts. Did quite on me while driving had to be towed. Was towed to my mechanic. When he went to check it, you guessed it, started right up but was running poorly. Found the coil wire connector was very loose. Secured it and started right up and ran great. Problem solved. NOT.
Still doing it. Come back the next day and it starts right up and runs great.
My mechanic just wants it to die so he can narrow it down to fuel or spark.
Its been in the shop twice, both a week at a time, started every time for him. No it does not have VATS. Fuel pump primes every time. Last time it left me stranded at work I took a spark tester and starting fluid back the next day but it started right up. Here is what I know or want to know;
1. Three relays on the Firewall, driver side---which one in the pump relay
2. Oil Pressure gauge always pegged above 60PSI
3. Will it not start if the fuel pressure is to low from a failing pump.
4. Can a bad oil pressure sensor/switch or coolant sensor really cause this
condition.
5. ICM - either it works or it don't Can it work/not work intermittently?
6. Where can I get a good manual for this car?
Thanks
Rich
The past two months it's been driving be crazy. Intermittent starting. It will go a couple of days and then it will not start. And when I say wont start I mean the will turn over but it wont fire. Let it sit and come back, hours to a day, and it starts. Did quite on me while driving had to be towed. Was towed to my mechanic. When he went to check it, you guessed it, started right up but was running poorly. Found the coil wire connector was very loose. Secured it and started right up and ran great. Problem solved. NOT.
Still doing it. Come back the next day and it starts right up and runs great.
My mechanic just wants it to die so he can narrow it down to fuel or spark.
Its been in the shop twice, both a week at a time, started every time for him. No it does not have VATS. Fuel pump primes every time. Last time it left me stranded at work I took a spark tester and starting fluid back the next day but it started right up. Here is what I know or want to know;
1. Three relays on the Firewall, driver side---which one in the pump relay
2. Oil Pressure gauge always pegged above 60PSI
3. Will it not start if the fuel pressure is to low from a failing pump.
4. Can a bad oil pressure sensor/switch or coolant sensor really cause this
condition.
5. ICM - either it works or it don't Can it work/not work intermittently?
6. Where can I get a good manual for this car?
Thanks
Rich
#2
Re: 88 IROC Intermittent starting problems
Do a search for various different problems that people have had. Your problem sounds exactly like mine. Ultimately replaced all 8 injectors, and the problem never came back. ....but that doesn't mean you don't have another issue. Food for thought. The Haynes manual gets a bad rap, but it's helped me through several problems through the years.
#3
Re: 88 IROC Intermittent starting problems
Do a search for various different problems that people have had. Your problem sounds exactly like mine. Ultimately replaced all 8 injectors, and the problem never came back. ....but that doesn't mean you don't have another issue. Food for thought. The Haynes manual gets a bad rap, but it's helped me through several problems through the years.
Thanks,
Replacing the injectors is one thing I have not found yet. Looks like its time for a manual. thanks for getting back to me!!
#4
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Car: 1991 Z28 1LE
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Re: 88 IROC Intermittent starting problems
1. Three relays on the Firewall, driver side---which one in the pump relay
2. Oil Pressure gauge always pegged above 60PSI
3. Will it not start if the fuel pressure is to low from a failing pump.
4. Can a bad oil pressure sensor/switch or coolant sensor really cause this
condition.
5. ICM - either it works or it don't Can it work/not work intermittently?
6. Where can I get a good manual for this car?
Thanks
Rich
2. Oil Pressure gauge always pegged above 60PSI
3. Will it not start if the fuel pressure is to low from a failing pump.
4. Can a bad oil pressure sensor/switch or coolant sensor really cause this
condition.
5. ICM - either it works or it don't Can it work/not work intermittently?
6. Where can I get a good manual for this car?
Thanks
Rich
bad coolant sensor can cause starting issues. Fuel pump has a fail safe wired into the oil pressure sensor, so also possible, though since your sensor is moving I would count that as unlikely.
ICM can be intermittent, with them failing when hot, and then after cooling down work again.
If it were me I would be looking at the distributor and ICM as a likely culprit. Next time it does it see if you're RPM gauge is bouncing while you're cranking.
Heat can also affect injectors you could Ohm test them when the engine is cold, and check them again after it shuts itself off again. You want somewhere between 12-16 Ohms of resistance.
Same for the fuel pump with heat, check pressure when cold, check it again when it shuts itself off again.
Haynes is not a bad manual to have lying around.
#5
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Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: 88 IROC Intermittent starting problems
Do a search for various different problems that people have had. Your problem sounds exactly like mine. Ultimately replaced all 8 injectors, and the problem never came back. ....but that doesn't mean you don't have another issue. Food for thought. The Haynes manual gets a bad rap, but it's helped me through several problems through the years.
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Car: 88 IROC Z/28-under re-construction
Engine: 5.7 Tuned Port
Transmission: It's in there....
Axle/Gears: 9 bolt Borg-Warner
Re: 88 IROC Intermittent starting problems
weak oil pressure sending unit signal to ecm ?