Check Engine Light

[Lance Link]

The little engine symbol came on today in the Yukon. It's solid, not blinking. I checked the oil (it's fine) and visually scanned under the hood for any loose hoses & such but came up empty. It's running fine.

 

I can't bring it to the dealer until Friday- I'm just going to run it. Any thoughts or suggestions?

 

[frdfandc]

The check engine light is the computers way of saying that a sensor (either mechanical monitoring or emissions) has either sensed a problem or failed. It could be even something as stupid as leaving the gas cap loose or filling the truck up with fuel while the engine is running. As long as the truck is running ok, no performance problems, drive the truck till your appointment.

[Shaners]

It could be even something as stupid as leaving the gas cap loose or filling the truck up with fuel while the engine is running.

That is exactly the first thought that came to my mind. If this is the problem, then make sure the fuel cap is tight and drive the truck for several "cycles" and it should clear the code...

[k1500chevy97]

Also make sure all the sensors are connected i had a wire clip pop off one of my O2 sensors .

[BlackSilver]

Hit the OnStar button and have them run a diagnostic (I think SLT comes with OnStar?). Got a check-engine light shortly after I bought my DuraMax, and their diagnostic returned a code for no power to the glow-plug ckt. Quick check found a loose connector.

[LogixRat]

It could be even something as stupid as leaving the gas cap loose....

Unfortunately I can admit to having been diagnosed with this problem on my 98 truck. Needless to say I felt like over it being something so minor and irrelevant. Oh well, live and learn. But now you can be sure I twist until I hear clicks.

[Lance Link]

Thanks, All- I'll check out the gas cap theory as well as the Onstar idea. Thanks for the input.

[Lance Link]

Ahhhhh... the wise members here at GM-TC have proven their worth yet again. My wife unscrewed the gas cap and put it back on again and the light went off shortly thereafter.

 

[99silveradoz71]

A simple and free solution, you've got to love that