Help needed please 2003 tahoe 4.8

[usp55]

hey guys,

I don't know where to start: bachelor party in Vegas last weekend, layed off tuesday, car wouldnt start yesterday!! life changed really quick.

Went to start my car and it cranked right over but wouldn't start. Sat all night and i had 14volts, no flickering lights, strong crank. Raining so I couldn't hear the fuel pump or relay click but this is my initial thought.

after 4 tries it fired up and seemed fine. 20 min of highway driving and im on the gas at 65 and i feel the petal go weak and i cant give it gas for a second or two. quick panic and then i had gas again. its did this twice to the store and three times coming back.

on the way home i was coming through me neighborhood low speeds and this time after it cut out I could her a hum from my engine compartment. dash lights off, battery light on, had to turn the key in the ignition to get it started this time.

fuel relay
fuel pump
ign switch
crank sensor
anything else?


Im thinking its a fuel issue but wanted to see what you thought. I really appreciate any help of thoughts you might have.

[NHRABill]

I have no experience with that truck but on the smaller v6 Pontiac I had the BCM got wet caused no start and all sorts of odd things look for a missing body plug wet carped check wiring harness for moisture that sort of thing. I had it still under warranty fix but had heard others with my old ride had similar issues. GL sorry to hear of your troubles

[usp55]

Thanks. Well it did rain a ton today but I've never had a problem with rain before.

Fuel pump makes the strangest shuttering noice when it primes but I dont always hear it prime. I don't have any fuel at the schrader valve either. I'm really thinking its the pump.

[V]

check for moisture in the distributor cap, had something similar with my 99 yukon

edit: nevermind, you should have individual coils.

[Dudbird113]

Undue the fuel filter and then try priming it and see if she pisses

[Mezzy]

Assuming no check engine light means it's not in the computer. Go back to basics checking for constant spark, fuel and compression. Assuming compression is fine, look towards a fuel or spark related issue. Could be as simple as a semi clogged fuel filter, to a bad ignition wire(could have moved and gotten burnt in a spot which would affect it in wet conditions), or just a really bad set of worn plugs. You didn't give much info like when it was tuned up last, or if the check engine is on/off. Check for proper fuel pressure. These results will tell you alot about what's going on and where to look next. Good luck.

[Stevoone]

I've done a few fuel pumps on those trucks. If you don't have a fuel pressure gauge carry a can of carb cleaner or starting fluid with you. When it acts up and won't start spray a little into the throttle body and it if starts then dies it is most likely related to the fuel pump.

Sometimes a good smack to the bottom of the fuel tank will get the pump moving again. We've had trucks towed in that wont start and I've gotten them started after hitting the tank.

[usp55]

Sry tuneup last fall plugs wires the usual stuff. No engine codes on the scanguage. I just took the fuel filter off and primed the pump but nothing came out.

[usp55]

Thank you to everyone that helped out. I dropped the tank and put in a fuel pump today. Running better then When I got it. Oil pressure is about 5psi higher too not sure why but hey it's right in spec now too. Again thank you.

[greenformula92]

good to see you got her running good. these trucks are known for fuel pump issues from the early 90's on up