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I regrounded my maf and I have 2 mV now. I'm not sure how much voltage I should have on terminal A. Books says 0.7 V - 1.1 V depends on airflow.
I know B is the ground and C is always 12V. I'd need to know the correct voltage on A cause I still have rough idle and car stalls with cold engine.
Now I have 1.7 to 3.4 running engine depends on rpm.
Is it correct or I should change the maf?
Please help.
 

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You should be reading 1.3 - 1.7V between terminal "a" and ground at idle with the engine warmed up. Is this how you were getting your readings? Also, the FSM says you should be reading less than 1.0 with the ignition on but the engine not running.

If your readings are still high, you might take a look at the MAF hot wire to see if there is any dust or anything unusual looking. Careful, it's fragile.

Your MAF reground sounds successful, just make sure all the wires are making a good connection in the MAF terminal. Sometimes they pull out because of that danged little boot.

If all this checks out, you probably have a different problem causing your idle woes. There is some a diagnostic routine avalable on SE-R.net.

Good luck,

Bill Conner
 

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What's the max voltage on a MAF sensor, and is it a linear increase as airflow increases? ie, could you possibly install a MAP sensor with the same or nearly the same 'curve' of voltage for airflow (read: manifold pressure for my map) and do away with a finicky MAF?

Probably not since at cruise a MAP will be reading nearly 20 inches of mercury while a MAF will be reading total airflow... nvm, answered my own question.
 

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Not no readings, low readings... and that would mean no/low fuel.

Think about it, MAF voltage increases with airflow. The higher the engine revs, the higher total airflow is. But manifold vacuum increases with rpms, especially at higher cruising rpms. I can cruise at almost 22" Hg while the car idles at about 18" Hg. So the MAP would be telling the MAF-calibrated computer total airflow is less than at idle because MAP voltages are linear via vacuum, not airflow. The reason it works right for me is that I have a table of cells that the computer uses for lookup - say 3500 rpm and 20" Hg, that means I get a pulsewidth of something like 200 ms. Airflow is approximated by rpm and vacuum in my case whereas it's approximated by the maf sensor directly (sort of) in maf-equipped cars.
 
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