GMC Yukon Denali Problem Report
GMC Yukon Denali Check Engine Light Due to Gas Cap Issue
A Loose or worn gas cap may cause Check Engine Light to illuminate.
check engine light came on and message appeared that the gas cap needed to be tightened. had diagnosised to determind gas cap was no longer sealing properly- replaced gas cap, but check engine light still on - hockeymom18
Engine light due to gas cap - Visitor
Gas cap sensor triggers check engine light. Despite replacing gas cap at the dealership the light goes back on. - Visitor
Gas Cap Seal - Visitor
wire that connects to rear window defogger has broken off - Visitor
check engine light - Visitor
Worn gas cap causes check engin light to come on. Only the $25 GM cap works to fix the problem. - Visitor
"tighten fuel cap" persistent problem, replaced cap, replaced tank vent solenoid (that fixed the slow fuel fill problem). Cleared faults for about a month then get a periodic "tighten fuel cap" and check engine. - Visitor
Engine light on. - Visitor
My check engine light came on and i took it in to get it diagnosed. it was a gas cap leak. they replaced it with a factory gas cap. i had an aftermarket locking cap before. - Visitor
MIL light comes on right after I fill gas tank and drive at speeds over 70 MPH. New O2 sensors, New air filter, new spark plugs, new plug wires, and I still get a P300 trouble code. (Random multiple mis fires). No help from Dealership other than an offer to TRADE IN TO buy "THE NEWEST CROWN JEWEL". Well, BS to that... - Visitor
I got a message on dash telling me to tighten the gas cap. I thought this was strange sine I hadn't gotten gas for about a week. Anyway, I tightened it for chuckles. Next day, I got the same message and did the same thing. Then I got the indicator light for the gas. I called on-star to do a diagnostic system check. They said tighten the gas cap and if the problem persists, go to the dealership for service. - Visitor
1)"Tighten loose gas cap" warning message came up twice in the message display. 2)"Engine light" illuminated on the dash cluster. 3) Gas cap WAS loose, re-seated & tightened cap - haven't replaced, yet. Will recheck this PM. - clemski
I have an 08 denali with the WORST gas cap. It is very hard to get it to seat flush. I constantly get the check engine light because it doesn't create a seal when it's on. - Visitor
Check engine came on. Onstar said it was not a serious problem. I replaced my gas cap with a new one and after several days, the light went away. Onstar said no proplems. - Visitor
check engine light stays on and odometer malfunction
I replace the gas cap but the light still keeps going on and off
i just put a new engine in a 1999 gmc yukon denalie it has a rebuilt transmission with less tha...
Fuel milage has decreased significantly due to such.