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Dan, Technician
Category: GM
Satisfied Customers: 24468
Experience:  Independent Shop Experience, 2 Year Automotive Diploma, & Access to Information Database
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2004 GMC Yukon Denali: The check engine light came..fuel system

Resolved Question:


I own a 2004 GMC Yukon Denali. The check engine light came on and I took to a local Pepboys to have it checked ... the code read out said something about the fuel system. The comments read "possible sticking purge valve or vent valve. Both are working normally at this time system is holding vacuum at this time" ... but unfortunately the check engine light remains on.

Could this be the problem and should I just go ahead and have those things replaced even though they said they're working normally or could it be something else?
Submitted: 6 years ago.
Category: GM
Expert:  Dan replied 6 years ago.

Welcome to JustAnswer, my name is XXXXX XXXXX I'm here to help get your problem resolved. Ask follow up questions, thanks.


Since this is a emission related code and has nothing to do with the performance of the vehicle I'd wait.....It could have just been a lose gascap. Let me know if you have questions, thanks.

Customer: replied 6 years ago.
A friend of mine said the same thing ... you think I should try to replace the gas cap?
Expert:  Dan replied 6 years ago.
That is the most common cause......Then its the vent solenoid, then the purge solenoid......All easy parts to replace...But you could end up replacing all those parts and find out the filler neck is leaking....Let me know if you have questions, thanks.
Customer: replied 6 years ago.
OK thanks Dan. Last question ... It's up for inspection soon so do you think I will have problems passing with that code read out
Expert:  Dan replied 6 years ago.
You will have problems if the problem is there when you bring it in. But as of right now check engine light is off you should be ok....I'd even consider bringing it in early while light is off if possible.
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Customer: replied 6 years ago.
ok thanks for your help