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Quick question on condemning this MAF sensor. Neighbor asked me to check his MIL on a Buick 3.8 (LeSabre I believe). Found a P0102, scan tool displays 0g/s at all RPM ranges. Had battery voltage when measuring across the pink and black and 5v measuring across the yellow signal wire and ground. I did not have my DVOM that measures Hz with me, so my question is, is the 5v on the signal wire and the battery voltage across the power and ground wires to the 3-way connector enough to confirm circuit integrity and condemn the sensor? Thanks.
The short answer is I don't know it is one of those jobs you really need to some idea of the signal frequency As you suspect it could very likely be the output isn't getting controlled by the internal circuit in the MAF but there is an outside chance it could be internal to the pcm . Stuck wothout tools I would gamble on a MAF but like you would feel uneasy until I saw it working.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Yeah I felt uneasy also. But I thought about it and figured if the 5v was there the MAF should pull it down. I'll bring my other dvom home and double check. thanks.
You're likely safe to install a new MAF, but I have a couple questions. Were your voltage readings taken while backprobing the sensor, or disconnected? Engine off, or running?
front probe key on engine off. my good dvom and backprobes were all at work. also with engine running reading was the same. i didn't see any point in checking frequency at the time since i had a 0g/s reading on the scan tool but I later had afterthoughts that it wasn't a 100% call.
