'Service Engine Soon' light O2 sensor?

[afishinado]

Just bought a '02 Z71 Tahoe w/55,000 miles. For the first time in my life I saw this dreaded light come on this morning. I read that it's most likely the O2 sensor is bad or I got bad fuel or the gas cap is bad... How long do the O2's last normally. My 97 Tahoe went 137,000 miles and I never saw the light come on... Not cherishing the idea of bringing it in to a dealer. Someone said Auto-Zone will check the codes for free???

[mnl119]

Just had the light come on on my 2003 Yukon (44 kmiles). A quick trip to Autozone reveled that the gas cap was the problem. I reset the codes, tightened the cap, and all has been good for the past two weeks. Try resetting your codes (disconnect the battery for 15 minutes), tightening the cap and see if it comes on again. Can't hurt and it's cheap.

[afishinado]

Try resetting your codes (disconnect the battery for 15 minutes), tightening the cap and see if it comes on again.

<{POST_SNAPBACK}>

 

 

Thanks.... Looks like I need to head down to Auto Zone, the reset didn't help.

 

Edit.. On the way to Auto Zone, stopped for a ice-cream cone

Light didn't come back on We'll see what happens before I do anything else! Thanks again!

[mnl119]

Best of luck! The Autozone guys were very helpful in my case.

[05Quadrasteer]

If it is an O2 sensor get under your truck and see if you can swap it out yourself. Might as well save all those labor fee's a mechanic is going to charge you. Looking at mine I can easily get to the back O2's, the front ones would require me to pull parts of my exhaust system apart to get at them.

 

Have a nice day.

 

Bill

[rebel77]

I am having the same problem. 2003 Z71 with 40,000. The code says the 02 sensor. I need to get it checked out. I can get to the one side the other side needs

exhaust parts removed. Of course that is the side I need to change. My light also

goes out, but comes back after a few trips.

[fossil]

check your warranty booklet. anything related to emssions control has a mandatory 5 years/80,000KM warranty on it, including spark plugs. Maybe even more now a days.

[kdm101]

I just replaced my O2 sensors this past weekend. I had no difficulty reaching them at all - no exhaust parts in the way. The hardest part was the left front connector. It was attached via a clip to the trans cooler lines tucked up into the transmission hump. After 7 years and 75k miles, they came off amazingly easy - just need a few minutes with penetrating oil and they cracked free.

 

If the SES light went out, I'd say you had a transient condition that set the indicator. After a few cycles of the engine, the condition didn't resurface so it was reset automatically. You can still head in and get the codes read for good measure as there's no harm in it.