I have a 98 Silverado with 5.7, it was recently in an accident, but the only damages are the airbags popped and the plastic under the bumper got broke off, well when i finally got home to check it out the battery was dead, jumped it, it started fine, drove fine then i parked it, next day it fired once and hasn't started on its own since.

Here's what I've done and checked out: NEW fuel pump, filter, pressure regulator, crank sensor, ignition module. Fuel pressure reads 61 psi and holds. Has blue spark. And will start with starting fluid down TB. All fuses and relays are fine. I shouldn't have thrown parts at it, hoping for a quick fix. So whats left? Injectors or PCM?

Also, once when pulling fuses on it the truck started cranking over on its own, no key in ignition, keys were in my pocket, had to loosen battery cables to stop it, but hasn't done it since...

 

When you put starting fluid in the TB, does it start and stay running or does it run for a few seconds and stop?

 

If it stays running, the fuel system is draining back to the tank is a likley problem. What isn't clear to me if what oldchevy is asking, and what I am stating, if the fuel is draining back to tank, the fuel pump should pressurize the system with key on. Do you have a weak crank, as in low battery when trying to start?

 

No, it dies once the starting fluid is burnt up.

 

I've used a couple new batteries to crank over, I've been trying to figure this out for about a month now.

 

I also forgot to add that after cranking for a several short bursts, the plugs are still dry as can be...

 

Well, I'd say PCM since none of them are fireing. You could put a pick test light wihile cranking no lights not power. I don't have a 98 book, but 99 shows pcm controls the injectors. I've had a misfire issue with one injector on my 3.1, but it was just one.

 

I have a 2000 GMC K2500 with the same issue i have tried everything. It has spark cranks has 65psi fuel pressure, it is as if it has no fuel injector pulse. I can try to start it and then pull a plug and its dry. So its like its got no fuel but has 65psi at the testing port. Spark is blue and we have the battery on a constant charge. I have also tried 3 different ECUs all with the same engine and transmission out of the scrap yard.

 

any dtc?
you need a crankshaft signal for injector pulse....monitor rpm data with a scan tool and crank the engine over. you should see approx. 200 when cranking...if you get zero rpm there is no crank signal to the pcm

 

Thank you. I need to run the tests but i need a better scan tool first. no dtc's at this point but it has been un hooked from the battery for a while. I got the truck as a not running if you fix this you can have that trade. Hoping to make it worth more then scrap




Update. Borrowed a buddys autel scan tool comes up with 175-185 rpm when cranking. Still lost.