1988 chevy c1500 no start after starting. - Diesel Forum

rockets10510 · 10-06-2009, 09:31 PM

grand pa has a 1988 chevy c1500 it started and ran fine one day and the next day he starts it drives to church and it will not start after church. finally got it started after pouring gas in to the intake. so we were thinking a fuel problem. no not a fuel problem. when we got it home we tested the pump the book he has said the pump should output between 9-15psi, the pump puts out 14 psi. then we tested the coil according to the book it passed. then we replaced the cap and roter (they were pretty bad). that did not help. then he took tin ignition module off and had it tested and it tested good. we are at a loss.

when the truck sits over night it will start right up in the morning, but when you cut it off and try to start it again it will not start.

so this is what we tested and replaced so far:

1. fuel pump tested good at with a pressure of 14psi
2. replaced cap and roter
3. had the ignition module tested and it tested good.

what else could it be. we dont know what else to try.

thanks for the help.

anthony

short_stuff · 10-07-2009, 06:00 PM

Assuming it is cranking over, just not firing, it sounds like an electrical issue when the motor is relatively hot (or warmed up).
When you checked the ignition module, was it when the truck was cold, or had it been running (and warmed up), and then taken out to be tested?
I had a 1984 Nissan truck that had a cold solder problem on the fuel pump. When the motor was cold, it would start fine. When it was warmed up and shut down, it would not pump gas from the tank to the motor. Traced it to a cold solder joint on the electronics on the fuel pump. Cold, it tested fine. Warmed up, no power in the pump. I replaced the fuel pump and problem solved.
Maybe your fuel pump is testing ok when cold, but not when warmed up?
I would be suspicious of the ignition module or the fuel pump.
Also, with a truck that old, be sure and check all of the vacuum lines to make sure they aren't cracked and sucking in air when they shouldn't be. I've seen that cause problems in the past with my parent's mid-80's Oldsmobile. When the lines were cold, the car would start. Once it was warmed up, it would stumble for a while (especially if you put the gas on it to go), then it would just about die. after it warmed up, there was too much air being sucked in from all of the cracks, and it would just spin without firing.
Have you tried to see if there are any codes being thrown out?
just some things to ponder.

short_stuff

da-bees · 10-07-2009, 06:20 PM

I am aware you stated "not a fuel problem"but I didn't notice if you have tried adding gas or starting fluid at intake since getting it home. Therfore I relate a past experience where I spent months testing and replacing parts while the problem was a tiny fuel filter in the carb inlet which I failed to notice. Look very close.

**bugman** · 10-07-2009, 06:26 PM

I would say that it is the control module. I had a 89 GMC company truck that would run fine until you shut it off then it wouldn't restart until it cooled off for a while. My problem was that I had to drive it 70 miles one way from town to town. I used to call a repair shop and tell them if I didn't check in with them to come find me, then on the return trip I would do the same with another shop. It finally died and wouldn't restart and they got to check it while the truck was hot, problem solved.

Kartek · 10-07-2009, 08:28 PM

I'd be curious to hear a solution to this as well. I have a '90 Chevy 1500 with a 350 and it does the same thing. On mine, I can pour a tablespoon full of gas into the throttle body and it starts right up.

I've been suspecting gummed up injectors...