'97 C1500 5.7 V8 Odd problem

[DocBernard]

Ok, I have been reading the threads about "Crank, no start" issues.....but mine is doing something weird.

Was at a light day before yesterday, went to accelerate and it just died. No warning, been running great for the past year since I got it. I coasted into the parking lot, thinking it might be out of gas. Nope 3/4 tank.

Checked fuel pump and filter......all good. Checked pressure at the top where lines go in to throttle body area.....lots of pressure. Pour a little gas into the throttle body, fires up....runs off that gas. Same with starter fluid. but dies as soon as that is used up. All fuses are good.

So, it's gotta be something on the top end of the engine......any help?????? I'm not the greatest mechanic and have limited tools.....but I can change throttle bodies/radiators/water pumps/etc. It's not pump, relay, filter....

 

[618 Syndicate]

Is the security light on the dash on?

 

[DocBernard]

When you first turn the key it comes on like normal then goes out and stays off

 

[DocBernard]

Just coming back from parts store. Maybe Mass air sensor? It threw that code, but I never heard of a complete no start condition from a MAS.

 

[618 Syndicate]

Ok.
If it'll run on ether or poured gas it's not a timing, compression, or spark issue. Only one thing left, fuel.

 

[1998_K1500_Sub]

Ok.
If it'll run on ether or poured gas it's not a timing, compression, or spark issue. Only one thing left, fuel.

Yeah, "fuel".

So why no fuel?

- ECU not firing the injectors (either intentionally or because of internal failure)?

- injectors not receiving fuel (OP says "pressure" is there)?

- injectors firing and delivering fuel, but delivering insufficient fuel for some reason?

 

[Dariusz Salomon]

Mine was doing something weird like this when tank wasn't full/over 3/4s. So I keep it topped and it doesn't do it. But it's easy for me cause I run on propane-you'd have to keep filling up. But for testing purposes try to fill it up and see where it gets you.

 

[DocBernard]

It’s got 3/4 fuel. And great pressure at the block

 

[DocBernard]

Mas code on reader gone. Just replaced that.

 

[DocBernard]

But did not fix issue