check engine light on ...but truck runs great
If your gas cap isn't screwed on tight, it can cause the check engine light to come on. I was also told by my mechanic that the sensor for the EGR valve on the Troopers is very sensitive. It can react even when there is no real problem with the EGR valve. But cleaning the EGR valve may minimize this problem. Chances are, the light will go out by itself after a few days. Mine did. Apparently it's not a huge emergency unless the check engine light begins to flash. Then it's time to get thee to a mechanic, pronto!
There is a manual reset behind the trooper dash gauges, you have to remove the guage cluster to get to it.
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