MAF Output

[cjcwi87]

What kind of output does the MAF sensor send to the ECM? Is it varying voltage or frequency? I always thought it was voltage changes required to maintain the set temperature of the sensor wire when airflow cools the wire. A friend said its varying frequency as the airflow cools the wire. Whats the deal???

CJ

 

[TurboDave]

In the stock Buick sensor it's a variable voltage being sent to the computer. THis is after the circuitry in the MAF has converted the variations in voltage across the resistor.

 

[cjcwi87]

Thanks Dave. I was shown a website page (I can get the URL) that stated some GM, Toyota and Fords that use MAFs sent a frequency based output to the ECM. The frequency varies directly with the amount of airflow. I am having trouble buying into it. My buddy did try to measure the voltage on the MAF output wire and couldn't get a reading, so there may be something going on here. Maybe two systems. Don't know.
CJ

 

[Eric Stage I]

The MAF is frequency output 30-150hz.

 

[TurboDave]

Thanks Dave. I was shown a website page (I can get the URL) that stated some GM, Toyota and Fords that use MAFs sent a frequency based output to the ECM. The frequency varies directly with the amount of airflow. I am having trouble buying into it. My buddy did try to measure the voltage on the MAF output wire and couldn't get a reading, so there may be something going on here. Maybe two systems. Don't know.
CJ

Trust me, it's frequency based. My O'scope doesn't lie.