Racer X79

Hey guys, I'm having trouble with my 72k mile '88 IROC. It starts up just fine, it will run perfect for as long as I drive it (10 min. to 3 hrs.)......BUT.....as soon as I turn it off, it will not start. It has spark, there is fuel at the schrader valve on the fuel rail, and nothing in the air intake is restricted. If I try to re start it after a couple minutes it will fire, run like crap (500-900 rpm), it will not respond to any throttle input, and then die. If I let it sit 15-30 minutes it will start right up, run perfect again until I shut it off, and then the whole process starts over again. The IAC was loose (I unscrewed it by hand), I replaced it with a new one and it does the same thing. Any ideas would be appreciated, I kinda spent my budget on the car and don't have a whole lot of $$$ left to play with.

9manastacio

iTrader: (4)

check your fuel pressure,KOEO, and with the car running. Check for pressure drop, should hold pressure for at least 5 minutes i would say. My guess is your pressure is low.

HCR13

iTrader: (5)

It could also be the injectors, I would check the ohms when the car won't start. It should be around 14 ohms, no less than 10...

Racer X79

I forgot to mention that I already ohm checked the injectors and they all looked good, really good actually. I just got done replacing the fuel filter so I thought I would fire it up to see if I had any leaks. I had my wife turn the igintion key to on, and I felt the pump relay kick in and heard the pump run for 2-3 seconds. It fired right up and ran fine. After about a minute I had her shut it off, then turn the key to ignition on again. This time no click from the relay, no fuel pump, and no start. I'm going to change the relay tomorrow......hopefully that's the issue?!? (I'm also picking up the adaptor for my fuel pressure tool so I can check that too) Thanks for the help so far guys.

Racer X79

Ok, I changed the fuel pump relay and it started and ran great. I cycled it 14 times.....5 minutes running, 1-5 minutes off, restart. It worked great. Then the 15th time no start. When it was starting good it had 46lbs. fuel pressure w/ key on-engine off, and it had 41lbs. while running. The last restart it lost all pressure while running and died. Then with the key on and engine off it didn't build any pressure at all. I've read of similar problems solved by changing the ECM in the distrubitor, but I can't keep throwing parts ($$$) at it. It really seems like the pump is good, but it's not getting power. Any ideas?

Chevy86 IROC-Z

iTrader: (17)

. Electronic Control Module inside the dizzy? I believe you meant ESC Module (Electronic Spark Control Module). Try this first to see if your pump is bad. Look at a ALDL. On the very lower left of the port is slot "G". Run a speaker wire from a "hot source" ( constant 12 volts) a stick it inside the port. This will automatically send 12 vlts to the pump. If the pump turns on and sounds good, then you pump should be fine. This method is used to test the pump. Try this too. Turn on the IROC and drive it around. Then go home, turn off the IROC and try to turn it back on. If she fails, disconnect the battery and pull the head lamp switch to drain all lingering current in the electrical system. Wiat for about 1 minute then reconnect. Try to turn on the IROC. If she turns on fine, then you the issue lies in the ignition timing, or the fuel system. If she still runs slugish, then the issue could be with the pump or injectors. Are there any troublecodes?

Racer X79

Thank you everyone for the help. I think I've narrowed it down to the fuel pump. I can jump it "cold" and it works just fine. As soon as I start the car and let it run for 5 min. +, it randomly doesn't work. If I let it cool for 30 min. + it always works again. I'm worried it will eventually leave me stranded. I guess I know what I'm doing this weekend.....