Question about 2003 Chevrolet TrailBlazer

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SERVICE ENGINE LIGHT

I OWN 03 EXT TRAILBLAZER AND THE SERVICE ENGINE IS ON. I HAD IT RESTED ON A SIMPLE HAND SCANNER AND IT SAID THE O2 SENSOR OR CAT IS BAD. I DO NOT SMELL ANY ROTTEN EGG SMELLS SO COULD THE PROBLEM BE THE SENSOR. IS THIS SENSOR AN EXTERIOR OR AN INTERNAL ONE?

THANKS
GARY

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The sensor will be external and cats don't always smell like rotten eggs when they go. Also check as you will probably have a post converter sensor as well that sends a signal back to the main computer.

Posted on Oct 09, 2008

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