Just lost a full day's pay chasing a bad sensor reading

Honestly, I was working on a 2019 Duramax with a rough idle and the scanner kept pointing to the MAP sensor. Tbh I swapped it out with a new one from the parts store, cost me $140. Ngl the truck ran the same and the code came right back. Turns out the real problem was a tiny crack in the intake boot letting in unmetered air, something I should have pressure tested first. I wasted about 5 hours and that sensor money for nothing. Has anyone else gotten burned by trusting the code reader too much before doing the basic checks?

3 comments

3 Comments

caseythompson2d ago

Feel your pain on that one, I mean the scanner makes it seem so obvious sometimes. Got burned by a P0420 code last year, threw a whole new cat at it before I found the simple exhaust leak. It's like the computer gives you a blind spot for the simple stuff, you just want to fix the thing it's yelling about. Makes that lost time and money sting even more.

laura_chen412d ago

My buddy did that with a bad coil pack code once.

the_anthony2d ago

Man, that's such a classic trap to fall into. I was reading a forum thread last week where a guy did the same thing with an oxygen sensor code. He replaced both sensors before he even checked for an exhaust leak, which was the real issue. It makes you want to throw the scanner sometimes! The tool gives you a place to start looking, but it doesn't do the thinking for you. That pressure test or visual check feels like a waste of time until it saves your butt.