1990 5.7L Chevy Wont Start

Hi all

I posted this in another section of the forum but figure this is a much better location. I've looked through the forum and I'm not exactly sure if the problems I'm having are the same as others, so...

My 90 silverado 5.7L 4x4 was running fine until we took a trip up to PA. On the way back we stopped to get some gas and the truck didn't want to start. It would turn over but just wouldn't start up. I checked what I could at the time (air filter, plugs, etc) and after a while it finally just started. So we were back on our way home but had to stop at a rest area a little while later cuz nature was calling. I didn't want the same thing to happen, so we left the truck running. The truck ended up stalling. It finally started again (it always turns over) and we almost got out of the rest area except it stalled once more when I let my foot off the gas pedal for a moment. Long story short - drove the rest of the 300 miles home with my foot never leaving the gas pedal (an interesting and stressful trip). We got about 2 miles from home and the truck stalled and would not start again (i don't think I let my foot off the pedal, but I might have). A neighbor towed it back to our house and now it won't start at all.

I know the fuel pump is working because i can hear it running for a few seconds when the ignition key is turned. I figured I would start with the cheapest part replacement and work from there - so I replaced the fuel filter with no improvement.

I think it has something to do with the fuel system (the truck has Throttle Body Injection) - so I started there. Please note that I do not have any fuel pressure diagnostic tools. Of course, I am attempting to fix this with the least expense possible. What would you suggest is the cause of the problem?

Thanks!

How did it run on the highway? It might be a bad TPS unit, found on the side of the TB with 3 wires running to it. THis can be checked at a parts store. Another thing is to check and see if it has spark. Think, engine needs air, fuel, and fire to run. What makes all these things happen? Pull one of the plug wires off the plug and insert a screwdriver, hold it about a 1/4" away from the engine(metal) have a buddy crank it, you should get a BLUEISH spark, if not then pull your distributor cap off and remove the ignition module under the rotor and have it tested. Also, were in PA did you get fuel, (Breezewood) I would suggest a can of dry gas in the tank.

Thanks for the reply. It actually ran fine on the highway - didn't really have any problems. But i was also being very conservative with the gas pedal - not accelerating too hard and such.

This weekend I'm going to be checking everything I can on the truck. I'll check for spark and i'll look at the TPS, some other sensors, and I'll check the fuel system if none of that pans out.

I'll post an update on what I find on Monday - I know y'all will be on pins and needles for that update too...
:)

Thanks

Have you got this fixed? If not, I had a similar problem with my 92 K1500. It would just die while driving, and then wouldn't start up again. First, I replaced the ignition module. It ran for a couple weeks and then had the same problem again. Ended up replacing the distributor and haven't had a problem since. Good Luck!

same thing was happening to me, my fuel pump was still working but just with not enough pressure. i changed the pump and fixed it.

i haven't fixed it yet - so far all i have had time to do was change the fuel filter, distributor cap, rotor, wires and plugs - none of which worked. At least they needed to be changed, anyway. My next target is going to be the fuel pump. I had my wife crank the motor while I looked at the injectors and didn't see any fuel being sprayed.

I have the haynes manual but it doesn't talk about removing the bed, which I am thinking about doing to get to the pump. Does anyone have what could be considered 'instructions' for removing the bed?

Thanks

i haven't fixed it yet - so far all i have had time to do was change the fuel filter, distributor cap, rotor, wires and plugs - none of which worked. At least they needed to be changed, anyway. My next target is going to be the fuel pump. I had my wife crank the motor while I looked at the injectors and didn't see any fuel being sprayed.

I have the haynes manual but it doesn't talk about removing the bed, which I am thinking about doing to get to the pump. Does anyone have what could be considered 'instructions' for removing the bed?

Thanks
Drop the tank from below, bed removal is not required. Not to mention more work that just removing tank from below.

there are 8 bed bolts, the light pigtail you can unplug by the tag. the gas cap screws, and a ground on the gas cap filler neck. that should be it.

Thought that I would give an update in case I've kept anyone on the edge of their seat...

After replacing the fuel pump, fuel filter and pressure regulator the truck would still not start. Since I had already replaced the rotor, cap, wires and plugs, the only thing I hadn't looked at was the pickup coil. Ohming out the coil showed an open circuit so I removed the distributor and got the coil out. The thing was corroded really bad. Green scale all over it and the insulation on the leads was broken - it was just a mess.

So, after I replaced the coil, the truck started and is running like a champ.

Oh, in case anyone was wondering, I dropped the tank to replace the pump.

Thanks all

I'm having the same problem. Tell me about replacing the coil pick up? Did you have to remove the distributor shaft to replace the pick up?