That time I fixed a bad idle by soaking a MAP sensor in brake cleaner

Got a 2004 F-150 in last week with a rough idle that wouldn't go away. Customer already threw a new throttle body and IAC valve at it. I was about to start chasing vacuum leaks with smoke when I remembered an old trick. Pulled the MAP sensor off and found the internal screen was crusted with oil and dirt. Soaked it in a cup of brake cleaner for about 10 minutes, let it dry completely, and reinstalled it. Truck idled smooth as silk after that. Saved the guy like $300 in parts chasing. Has anyone else had luck cleaning sensors instead of just replacing them?

3 comments

3 Comments

paige3311mo ago

Respectfully, I mean brake cleaner can work in a pinch but it's pretty harsh on the plastic housings and rubber seals. Idk, I've had better luck just using electrical contact cleaner and a soft brush.

lilya761mo ago

Yeah I've had the same experience. Used brake cleaner on an old fuel injector connector once and the plastic got all brittle and cracked within a week. Switched to CRC QD Electronic Cleaner and never looked back. The soft brush trick works way better than blasting everything with harsh chemicals too.

west.richard1mo ago

Paige331 you're absolutely right about the brake cleaner eating up plastic. I learned that one the hard way on an old alternator. Those rubber seals get brittle fast if you use the wrong stuff. Electrical contact cleaner with a soft brush is all I use now too, keeps things from getting wrecked.