1997 K2500 Running Rich, Rough Idle, & No Start

[WasatchWendingo]

Hey all,

 

I drive a 97 k2500 p/u w/ 5.7L. I'm trying to diagnose all the problems listed above, but don't have a lot of experience (or money for that matter). As far as the no start problem, it will sit and crank forever, but the only way I can get it to start is by applying the gas pedal and even then it still struggles. In addition to all that, it struggles and stutters and just generally has no balls.

I thought it might be the fuel pressure regulator so I got a fuel pressure gauge and attached it to the schrader valve. When I turned it to accessory and let the fuel pump run, it shot up to 60 psi and then down to between 15 and 20 psi after a couple of seconds. When cranking it, it's at 60 psi as well.

Does anybody have any advice or idea what it could be or where I should look next? I'm kind of new to troubleshooting vehicles so any help would be great.

[barry G]

dropping to 15 and 20...

it may be dumping into a flood for some seconds.

 

bad injector(s)?

 

can you check engine codes?

checking spark plugs can narrow down which cylinder(s) are rich

[east3021]

If it is at 60-psi while cranking, that should rule out the fuel pump. It should hold pressure for a few minutes after turning the engine off. If it drops, you could have a leaking fuel line, bad regulator or leaking injector.

 

To check for a leak at the intake, you'd need to pull the upper intake manifold. Disconnect the coil's electrical connector, reconnect the fuel lines at the injector assembly and cycle the ignition switch a few times without cranking it. You should be able to spot a leak then.

 

But, since you're already there, it would be a great time to upgrade the spider to the MPFI unit.

 

 

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