94 5.7L TBI stumbling

[GMC1994K1500SierraSL]

Also I went through a quarter tank on fuel in about 100km


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[thunderstruck]

You can rent or buy a fuel pressure gauge kit with a TBI fuel line adapter. I use the Actron CP7817 kit, got it for around $30.

The adapter will fit inline near the fuel filter or throttle body.

Though, your problem sounds ignition-related, I always start with checking fuel pressure.

 

[GMC1994K1500SierraSL]

Hmmm ok I can try that, I'll just have to find where to get one, what's regular numbers? Oh and the threads on the nut that go into my fuel filter on the throttle body side is missing the 1st thread due to previous owner stripping it out, that could give me a$$ pain trying to pull that off and put it back in


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[thunderstruck]

9-13psi is normal, though I'd say 11-15 is optimal.

Doesn't matter much which side of the fuel filter you put the adapter as long as the filter isn't clogged, though you will have some more slack to play with on the throttle body side. You can also put it just before the throttle body, but it is a PITA since you will have to unbolt the bracket holding the fuel lines to the bellhousing. You also have to be careful to not crack the injector pod when tightening down the factory adapter.

 

[GMC1994K1500SierraSL]

I just put a brand new Fram fuel filter on it, I guess going from the back of it wouldn't be too bad, what parts are ignition related that could cause this? Its really weird, on Sunday it was stumbling, stopped, turned it off for an hour, jumped back in drove it fine, today I drove it 100km no problem, stopped at the parts place and that's where it was trying to die at idle, then stumbled all the way home, just started it after it was off for a while and it was fine other than the noise coming from the back of the motor I'm thinking distributor is making it or a part under it, the noise kinda got more noticeable now


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[GMC1994K1500SierraSL]

Tried to see sparking from the distributor in the dark nothing, but when it sits for a while and is started it smells heavily of gas from the exhaust


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[thunderstruck]

The intermittent nature of the problem makes me suspect the ignition coil, but that's just a WAG.

I'd change the spark plugs and wires since you don't know their condition. I'd also pull the cap and check for signs of arcing. Wouldn't be a bad idea to have the ignition module tested while you are under the cap too.

 

[GMC1994K1500SierraSL]

What brands should I be looking for? Delphi and AC Delco I see people say is good is that what I should be investing in?


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[slippy3002]

ACDelco ftw!

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[GMC1994K1500SierraSL]

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Couldn't get the AC Delco plugs because they would have to come from another warehouse and charge me another $20 for shipping, haven't pulled the trigger on this stuff but I think this what I'll get, how can I be 100% sure all this stuff is a perfect fit for my truck? I entered all the fields with the info for my truck on the site, I should be good right?


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