Original owner of an 04 Envoy XL V8 with 131k on it. Check engine light has been on solid for 7-8 years now. Code shows it's an O2 sensor but can't indicate which one(s). Vehicle has run fine all this time so didn't bother fixing.
Experiencing an issue last couple weeks. Starts up fine cold but begins running rough/sluggish 1-2 miles down the road and the check engine light starts flashing. If I keep driving after that, it begins running normally again and the light stops flashing. Sometimes happens when stopped at a traffic light and idles rough. I turn the ignition off and restart...runs fine after that.
Recall, in my deep grey matter, having a similar issue when the vehicle was still under warranty...took to the dealer. The service receipt said all they did was replace the gas cap. Thing has run fine all these years until recently.
Is it possible replacing the gas cap again could resolve the issue?
Experiencing an issue last couple weeks. Starts up fine cold but begins running rough/sluggish 1-2 miles down the road and the check engine light starts flashing. If I keep driving after that, it begins running normally again and the light stops flashing. Sometimes happens when stopped at a traffic light and idles rough. I turn the ignition off and restart...runs fine after that.
Recall, in my deep grey matter, having a similar issue when the vehicle was still under warranty...took to the dealer. The service receipt said all they did was replace the gas cap. Thing has run fine all these years until recently.
Is it possible replacing the gas cap again could resolve the issue?