Replacing or cleaning Mass Air Flow Sensor

surfcitysurfcity Member Posts: 1
edited February 2019 in Nissan
I have 2012 Quest SL. About 120K miles on it. A warning light came up the other day. The code shows it is about mass air flow sensor. I decided to clean the sensor first. If that doesn't help, I would replace it. Anyway, I looked the location of the sensor under the hood. It's located the way back, almost under the dashboard and its facing inside. What a poor design. There is no way I can reach it unless I remove the other parts and disassemble the cover that the air filter is in. Has anyone done this without taking apart? Thanks for your help. Best,


  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    Here you Go:

    Keep in mind, though, that just relying on the code to solve your problem may not work. The code doesn't actually prove that the MAF is bad, only that the circuit it operates in, is in some kind of dysfunction. It could be a wiring issue and, even more commonly, caused by vacuum leaks somewhere.

    The code P0101 means that the signal from the mass air flow sensor (MAF) is out of expected range. The MAF sensor is installed in the engine intake, right after the air filter. it measures the amount of air entering the engine through the throttle valve. The engine computer (PCM) uses the signal from the MAF sensor for operating the fuel injection system. When the car is accelerated, the throttle valve opens and allows more air to flow into the engine. The MAF sensor detects the air flow and sends the signal to the engine computer, which in turn commands the fuel injection system to add more fuel. Similarly, when low air flow is detected, the PCM reduces the fuel supply. The PCM checks the rationality of the MAF sensor signal by comparing it to the signals from the intake air temperature sensor (IAT), manifold absolute pressure sensor (MAP), throttle position sensor (TPS) and some others. If the signal from the MAF sensor is lower or higher than expected, the ECM detects a fault and stores the code P0101 in its memory.
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