i need help what would cause this? i go start my truck starts idles revs fine i put it in gear still fine get up to bout 15 mph acts like its flooding out it will clear up and run perfect as long as i dont shut it off if i do it does it all over again lets say i go to the gas station leave my truck running get back in it and take off runs great if i go to the satation and shut it off pump gas and pay get back in and boom does it all over again its a 1999 seirra 5.3 please help oh by the way i need help with my obdII port also no power fuses are good checked cig lighter its good idk

 

A period or two and some capital letters would make it a lot easier to read your post.

You said the truck acts like it is flooding, what other way could you describe what it is doing?

 

sorry bout that lol. when its acting up its only in gear, it wont go like its getting too much fuel flooding out. press the gas and it gets worse, ease outta the gas and u can feel it kinda clear up until u press the gas again,, then it will quit all togather. it runs fine after that aslong as i dont shut the truck off... i was born in northern illionis what part are u in

 

No mods or anything? Tune?
Does it run good even wide open after it clears up?

Has it been serviced lately? plugs, wires, fuel filter and the such?

 

it doesnt have a tune has cold air intake and true dual exhaust.. runs like a top when it stops when it shifts from second to third at wot it pops.... i havnt done plugs and wires or anything yet.... i havent had it long.. its acts to me like the computer notices the problem and corrects it . cause its fine as long as i dont shut it off ... could it be o2 sensors ? my obdII port wont work for some reason. ive checked fuses...

 

The OBDII port has two grounds, one power, and a serial to the PCM. Prolly a wire pulled out of the connector or broken wire?

I believe its 4 wires total.. maybe 5?

 

My opinion is fuel pressure. Could be lean, then when you give it enough gas to hit power enrichment,it commands a richer mixture which clears it up well enough to pull again. I've seen them lose their prime and have trouble starting again as well.

 

Mine popped when it shifted, when it was running super lean.

 

thanks guys if i cant get my obdII port workin i guess ima just start changing parts prolly start with o2 sensors

 

kelsey and me think that you should check fuel pressure 1st.