1997 silverado wont start.

97 SILVERADO 350ci. 131,000 mi

Out of the blue the truck wouldn't start. Was running perfectly fine before that.

Changed plugs, wires, cap, rotor.

Thinking that I had fuel problems I also changed fuel pump, and filter. Still wont start. The truck will run momentarily if I dump gas or starting fluid down it. I'm leaning towards fuel injection system. But not sure. Can anyone tell me what to look at.

Any advice would be appreciated.

Are you dumping fuel down the throttle body? You know your dumping fuel into the engines vacumm. Although I dont know if it can hurt anything, it's not a good idea.Did you hook a gauge to the high pressure supply side of fuel pipes? that would easily give rule out (or in) the fuel system.

Are you dumping fuel down the throttle body? You know your dumping fuel into the engines vacumm. Although I dont know if it can hurt anything, it's not a good idea.Did you hook a gauge to the high pressure supply side of fuel pipes? that would easily give rule out (or in) the fuel system.



Yes I was dumping through the throttle body. (oops). No I didn't hook any gauges up. Kind of a backyard mechanic. Don't have any gauges. Are there any other ways to narrow down what's wrong?

Thanks for reply.

Yes I was dumping through the throttle body. (oops). No I didn't hook any gauges up. Kind of a backyard mechanic. Don't have any gauges. Are there any other ways to narrow down what's wrong?

Thanks for reply.

Can you hear the fuel pump run when you turn the key on ?? If not check the fuel pump fuse and under the hood on the drivers side fender is a black box with a cover on it. The fuel pump relay is in there along with some other relays that are identical. You can swap one for the fuel pump with a different one to try that. If the pump is running it could be a bad pressure regulator diverting the fuel back to the tank. You will need a pressure gauge as skipr said to check that.

Can you hear the fuel pump run when you turn the key on ?? If not check the fuel pump fuse and under the hood on the drivers side fender is a black box with a cover on it. The fuel pump relay is in there along with some other relays that are identical. You can swap one for the fuel pump with a different one to try that. If the pump is running it could be a bad pressure regulator diverting the fuel back to the tank. You will need a pressure gauge as skipr said to check that.

Although you have a good point, I had a fuel pump that ran just like a normal one. But it had no volume output. Meaning it did discharge fuel, but at a very reduced volume under pressure.

And to anwser your ? on testing without a gauge. You could take the fuel supply line off at the filter and put a flexable hose on it and into a bucket (I do not reccomend this at all) Run the pump with the prime connector (under hood) and observe the flow. It should fill a 5 gal bucket in less than a minute easily. Very crude way of testing it.

Although you have a good point, I had a fuel pump that ran just like a normal one. But it had no volume output. Meaning it did discharge fuel, but at a very reduced volume under pressure.

And to anwser your ? on testing without a gauge. You could take the fuel supply line off at the filter and put a flexable hose on it and into a bucket (I do not reccomend this at all) Run the pump with the prime connector (under hood) and observe the flow. It should fill a 5 gal bucket in less than a minute easily. Very crude way of testing it.


o.k. had it tested. Plenty of fuel pressure. Any other suggestions on what to look at next.


Thanks

if you have a multi meter or know someone who does, remove wire connector at injector and check to see if it is getting a pulse, use dc volt setting and have someone crank the engine to see if any voltage change, if none you may have a wireing problem, blown fuse, relay, or bad ecm, if there is power use the ohms setting of meter to check the ressitance of the injector coil

I had a problem kinda similar to that, I took it muddin, got some water in the air box, and it wouldn't stay running and when it was it sounded realy bad and wouldn't let me give it any gas or it would die, I unhooked the oxygen sencer off the air box and it ran fine.