Redwool53

Sorry is this is answered somewhere else but my 1985 Iroc is throwing a MAF sensor code. We have back probed the sensor and it’s showing 0.5, 0.6 on a voltmeter at idle. Am I checking this correctly or do I need to do something else? Any idea why it would still be throwing this code?

Tuned Performance

iTrader: (92)

33,34 or 36 are you using the fsm trouble tree ?

Redwool53

34

Tuned Performance

iTrader: (92)

B11 at ecm or pin C at maf ? Do you have a scanner to see gps . I don’t have a fsm for 85 but I think it should be .80 in that range. No fsm ?

Redwool53

Idk what any of that means….. lol

Tuned Performance

iTrader: (92)

Are you using a gm helm service manual for troubleshooting?

Tuned Performance

iTrader: (92)

Vader

This is what the analog MAF output voltage is for an '86 305:



If the idle RPM is changed, the intake air mass will change, so that piece of information is critical to determine if your reading is relevant.

500-600mV could indicate a very low idle RPM, a lazy or under-reporting sensor, or unmetered air entering the engine (leaks) somewhere in the system.