Today I was chasing an intermittent misfire on an 05 Subaru Forester. P0301, 2, 4 codes. It was a weird one, the stumble/miss would come and go at random. Scoping it looked like a lean/no fuel misfire. I pulled the MAF and it was dirty so I cleaned it with a couple quick shots of brake clean then shake it out, like I always have. Reinstalled MAF and car now starts and dies immediately, every time. You could get it to stay running if you gave it quite a bit of throttle (50%+), but I managed to get an idle MAF reading of 86g/s. Tossed that lump of shit into the trash and the new MAF seems to have solved the misfire.
Been in the same situation with a Nissan. Lean trims, hesitation, scan data is screaming incorrect air measurement. It's a comeback on another tech, so we can't sell a MAF. I suggest attempting a cleaning, and the boss is all for it. :silly: A shot of brake cleaner later, and the MAF is d-e-a-d. Now we gotta eat a new MAF.
In both cases, I think the MAF was already on the way out. This is why I hesitate to clean a MAF any more, even with the specific MAF cleaner.
Brake cleaner is basically acetone...not plastic friendly.
CRC mass air flow sensor cleaner is a combination of 2 ingredients in making gasoline...plastic friendly. Isohexane a "cleaner" and trimethylpentane "100 octane".
Can't use CRC mass air flow sensor cleaner on Karman-Vortex sensors found on Toyota Supra Turbo, Mitsubishi, and most Lexus vehicles. (fine print on the can)
heyinway wrote: Brake cleaner is basically acetone...not plastic friendly.
Interesting I didnt know this,but I also never bothered to read its ingredient list either.Years ago I had bought two really expensive rims from a co-worker to mount on my brand new Mustang LX Notchback.Problem was,the clear coat was yellowed & peeling off in a bunch of places.I remedied this by using a half gallon of acetone + rags + 1-2 hours of my time + 1-2 hours of elbow grease. They came out looking brand new.After I was done,the only thing I had to do was make a trip to town to buy two new rims to match.The only reason I brought this up was to verify if brake cleaner will work just as well as the acetone that comes in a gallon can,since you used the wording "basically acetone"?? If acet
is the only ingredient,it should work just the same as whats in the can.Thanks for the info and any feedback.
Lean trims, hesitation, scan data is screaming incorrect air measurement. It's a comeback on another tech, so we can't sell a MAF. I suggest attempting a cleaning, and the boss is all for it. :silly: A shot of brake cleaner later, and the MAF is d-e-a-d. Now we gotta eat a new MAF.
This is why I hesitate to clean a MAF any more, even with the specific MAF cleaner. 
