2008 Yukon Denali P0442

[02Lightning]

I got this code, so figured it was a loose gas cap and I checked it and cleared the code. Code came back so I replaced the gas cap with an AC Delco one. It looked ok, but I figured it was 11 years old. I also ordered an AC Delco purge valve from amazon #214-1680 ($11.63), and I'll throw that on there too. Now I wait.

 

[swathdiver]

I got this code, so figured it was a loose gas cap and I checked it and cleared the code. Code came back so I replaced the gas cap with an AC Delco one. It looked ok, but I figured it was 11 years old. I also ordered an AC Delco purge valve from amazon #214-1680 ($11.63), and I'll throw that on there too. Now I wait.

Then there's the vent valve, Charcoal Vapor Canister and all the lines, near $500 worth of parts. I'm at the point of needing to put a smoke machine on mine to find the leak. Using the Tech-2, we determined that the vent and purge valves are ok and the leak is not between them. I bought a new gas cap and the code returned quicker! Put my old one back on!

 

[02Lightning]

Yes, I changed the vent valve and harness adapter a couple years ago. I think there is a sensor on top of the tank also. If I have to change that, I may put a fuel pump on it for all the trouble it is to get to. I'm at 122k.

 

[ford141]

Mine had that code at 130K. Had to take it to the dealer to diagnose with a smoke machine. Turned out to be the vent on the top of the fuel pump sending unit. It had a pinhole rusted through even though there was almost zero rust anywhere else on the Yukon. New fuel pump sending unit fixed it (replaced myself).

 

[02Lightning]

Mine had that code at 130K. Had to take it to the dealer to diagnose with a smoke machine. Turned out to be the vent on the top of the fuel pump sending unit. It had a pinhole rusted through even though there was almost zero rust anywhere else on the Yukon. New fuel pump sending unit fixed it (replaced myself).

Yeah, I hope I don't have to mess with that on mine. I changed the purge valve on the 9th, and light hasn't returned. So, I hope one of the two was my problem.

 

[dross99_si]

Good luck! Swathdiver and I are both still dealing with this EVAP leak crap. I've changed cap, purge and vent. Still came back. Most likely something on top of the gas tank. Interestingly enough right around the time I started getting the EVAP code the truck began having intermittent starting issues. Cold starts no problem. Usually after making the first trip of the day the next time I go to start it will crack it's ass off and quit. Turn key to off, try again, it cranks for longer than normal and eventually will sputter to life. Like it's either starved for fuel or flooded. One or the other. When it's running we have zero issues. Just a starting issue once in a while after heat soaked.

 

[mjreynolds928]

Good luck! Swathdiver and I are both still dealing with this EVAP leak crap. I've changed cap, purge and vent. Still came back. Most likely something on top of the gas tank. Interestingly enough right around the time I started getting the EVAP code the truck began having intermittent starting issues. Cold starts no problem. Usually after making the first trip of the day the next time I go to start it will crack it's ass off and quit. Turn key to off, try again, it cranks for longer than normal and eventually will sputter to life. Like it's either starved for fuel or flooded. One or the other. When it's running we have zero issues. Just a starting issue once in a while after heat soaked.

Did you ever find the problem? I am having a similar issue in my 2007 Tahoe.


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