bad gas or something else? 6.0 denali

[BeaverGod]

filled up with gas today went home parked for about 3 hours. decided on a trip to taco bell. go out start the car up everything is fine. start driving. turn left, obviously let off gas, yukon hesitates to engage in gear because the throttle wont respond but eventually does after about 1-2 seconds. drive normally.....turn right and let off gas to slow and turn....car hesitates badly once i begin to accelerate again. it feels like im pushing and letting off the gas on and off on and off while i accelerate. i pull into taco bell....the yukon nearly dies. i pull into a parking space and turn the car off thinkknng i mightve gotten bad gas. it starts up just fine but after about 5 seconds of ultra low 400, 300 rpm it nearly dies (down to 200, 100 rpm and shuttering). so i turn it off, turn it on and try to give it some gas and the throttle just doesnt respond at all. finally i repeat and check engine light comes on. i give up and have someone pick me up. pissed.

any idea what this could be? the yukon has not been symptomatic whatsoever to this point of anything. it just came out of nowhere after getting gas then letting it sit for a couple hours.

could it be bad gas? how would i be able to diagnose/fix this without a trip to the dealer? if possible....

any ideas on what it could be symptomatic of?

thanks
bg


it has an intake on it but its only about 3,4 months old. not a bad filter. also about 89,000 trouble free miles.

 

[ATL]

sounds like a fuel pump, go to the parts store and borrow a fuel pressure tester


also, quick thought, go outside and crank it up. if it sputters or idles low, reach under the truck and kick or hit the fuel tank and see if it gets better

 

[sumo]

could be a sticking Throttle body

 

[Rivieraracing]

My first guess would be what ATL says, but you could also try cleaning out the throttle body to see if that solves it, like Sumo says!! But I'd bet from what you mentioned that it's the fuel pump!!

 

[chauncey0337]

+1 on the fuel pump especially if the truck has been fine til now. I've heard the pump usually goes out after a fill up, go figure.

 

[BeaverGod]

It will be late day before I can kick it. What should I expect in cost to have a fuel pump replaced?

Thank you for your replys

 

[domin8]

Fuel pumps are rather simple to replace. The hardest part is dropping the fuel tank. It can be done in your driveway if you're proficient with tools. The pump itself is the pricey item. Expect to spend $200-$300 our more for it. However, I'd do what Sumo says first and clean the throttle body. It's easier and much cheaper. Just be sure to let it completely air dry before pouring it back on. If it turns out to not be the throttle body you'll be happy to know it's clean and not causing any problems.

 

[ATL]

shops charge 800-900 for a new fuel pump, or u can get a delco assembly from arts store for around 300. u can easily do the job if your willing to work on it for 4 hrs or so on a saturday. go to youtube and type it in, theres videos of how to do it

 

[Rivieraracing]

Yeah if you are mechanically inclined at all, do it yourself!! I think the dealership near me quoted $1200 for them to do it, and then continued that they no longer did the lifetime guarantee on the pump if they install it like in the past!! Needless to say I laughed at them over the phone before I hung up, got a OEM pump for a killer price, and 5 hours later got my truck up and running again!!

 

[WHITEOUT]

I would try the simpler things first, or cheaper that is. lol. Maybe try replacing fuel filter first also. Could have just sloshed up some sediment when you filled it up, plugging up filter. Do like others said also, clean throttle body, MAF, filter. I would try the easier things, before you go diving into a $300 fuel pump. My fuel pump is going, been to lazy to replace, takes like 2-3 cranks to get her started, but never hesitates during driving. Try the simpler, cheaper and easiest things first, then move to harder, more expensive things. IMO