Another thing is that after all the parts in my truck were replaced at the shop (see my temp gauge question) they said that the check engine light came on during the test drive, and that the code said it was the 02 sensor. They replaced it for the cost of the part. On the way out of the shop, after about 2 miles, the check engine light came on again. Now in all of my trials and tribulations with this truck, I have never seen the check engine light come on. I took it back, they checked it and said that the 02 sensor was the wrong one. They said that a specific so they must have sent this one. So they removed it and put in a new, universal one. Drove off, and the check engine light came on again, at the exact same place. Called the shop, they are ordering the specific 02 sensor and will replace it on Monday. Does this sound right? Something tells me that the light will still come on after they replace it with the specifically called for sensor. BTW - I watched them do the test, it came back as the 02 sensor.

 

OOOPS --"They said that a specific so they must have sent this one."
should have read "They said that a specific 02 sensor was required, but the parts house was out of stock, so they must have sent this one."

 

There are several codes related to the HEGO - do you know the number? What year is your truck? What engine? What mods? How many miles? (See a pattern? )