need help truck not running

[theTank77]

when was the last time you gave it a tuneup? when was the last time you put fuel system cleaner in it? go get a bottle of Seafoam and dump it in your tank then go fill up. let the truck sit overnight to dissolve all the shit in your fuel system start up your truck in the morning and let it run for a lil while. see if it runs better.

Fuel system cleaner is great, if you want your seals to fall apart in the next 500 miles.

Also, dont EVER put seafoam in your gas unless its the rare seafoam made specifically to be put in gas. The way you should use seafoam would be to add it to your oil, let the engine idle for 10 min, then drain the oil, and replace it. I really hope you dont put seafoam in your gas.

I've used seafoam in my truck for the past 3 years. i put a bottle in my truck every 3 months and I never have a problem. I do a full seafoaming in the oil, vacuum, and gas once a year.

[teardrop]

sry i edited also when you have your fuel pressure gauge on there does it hold the 50 psi after you shut the truck off ? if it don't then you ether have a leak in your line or a leaky injector or a bad fuel pressure regulator

Edited November 3, 2011 by teardrop

[barney91]

I can't pull any injectors because the injectors are under the upper intake manifold. Also my yukon doesn't really have injectors it has those poppets because I have the scfi type fuel system not the mfi which really has injectors

[teardrop]

you cant unplug the electrical plugs?

[barney91]

Nope the scfi system doesn't have electrical plugs and everything inside the intake manifold so I have to take it apart which I plan to do because I think its the fuel pressure regulator which I plan on replacing

I ordered the delphi fj10566 kit to swap my scfi system to a mfi style because the poppet style injectors have been know to clogg which I think is another part of the problem

[teardrop]

could be does your fuel system hold pressure when the truck is off?

[barney91]

I didn't check with the guage but I think it does because if I push on the vaule, fuel sprays out

[teardrop]

thats a good sign means your injectors and regulater is not leaking witch tells me your regulater is good sounds like its a cloged injector or 2 and it could be timming but if somthing was wrong in your timming i think a code would be present

[barney91]

Well what I don't get is why it only idles for 5 seconds then shuts off. It doesn't bogg out or anything as it shuts off its just turns off

[teardrop]

does it sound like its miss firing when its running or when you push the throttle