Q: How to know MAF sensor is working

asked by on August 15, 2017

How can I know if my MAF sensor is working or not, so that I don't waste time and money cleaning it if it doesn't work? I've heard from some that a quick way to know is with the car running if you unplug the sensor the car will turn off..some have said the opposite and that the car will not turn off. About a month ago a mechanic unplugged it and the car turned off..I tried it a couple of days ago but it did not turn off..so I'm confused right now. I want to know how besides using an ohmmeter . thank you

The best way to know if the MAF is working is to look at a data page on a scanner to see if the MAF is sending correct signal to the computer. Some MAF sensors have the inlet air temperature sensor or IAT sensor built into it and these types may make the engine run rough and stall when disconnected. Regular cleaning of MAF is considered maintenance and only takes a few minutes. This cleans off dirt and oils that accumulate on the sensor that can cause inaccurate readings. If you are getting codes to the MAF is another way to know it is not working correctly. When you disconnect the MAF on most cars the computer is designed and programmed to use other sensors to compensate to have the engine run as good as it can without the MAF sensor operation. It will also store a code and turn on the check engine light and may cause computer to go into failure management mode and cause loss of power and limit rpms and transmission shift function.

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