The mass air flow (MAF) sensor is an air flow meter that measures the amount of air entering the engine. The powertrain control module (PCM) uses the MAF sensor signal in order to provide the correct fuel delivery for a wide range of engine speeds and loads. A small quantity of air entering the engine indicates deceleration or idle.

A large quantity of air entering the engine indicates an acceleration or high load situation. The MAF sensor has an ignition 1 voltage circuit, a ground circuit and a signal circuit. The PCM applies a voltage to the sensor on the signal circuit. The sensor uses the voltage in order to produce a frequency based on inlet air flow through the sensor bore. The PCM uses the barometric pressure, air density, manifold pressure, throttle position, and the engine RPM in order to calculate a predicted MAF value. The PCM compares the actual MAF sensor signal to the predicted MAF value in order to determine if the signal is stuck based on a lack of variation, or is too low or too high for a given operating condition. DTC P0101 will set if the actual MAF sensor signal is not within a predetermined range of the calculated MAF value.
Possible causes for this code are:

  • Faulty sensor
  • Broken wires at the sensor connector. Tug on each to see if it stretches or breaks
  • Loose air intake duct or breather hose / tube between the MAF sensor and the engine
  • Dirty sensor. Try spraying cleaner inside the sensor, then take for drive to "Blow out" the cleaner

Related Auto Repair and Information

Related Automotive Information

Be Social With Us !

Leave your comments

Post comment as a guest

    • Guest - Andrew

      Hi I got p0101 code in a Nissan sentra I wonder what it is

    • Guest - Matt

      In reply to: Guest - Andrew

      Like this article states- sounds like you have a mass air sensor problem. You can try cleaning it, but that usually does not work. If the wiring is OK, You would have to have it replaced.

    • Guest - JIM

      I'm getting p0101 and p0131 constantly on my 2000 grand am. I seem to be lacking power sometimes, and I've had it twice now where I have no power in overdrive. I litterly have to floor it and get into passing gear to get my car to accelerate. I already changed the EGR cause I had that one coming up too. But the problem is still there

    • Guest - Frank

      In reply to: Guest - JIM

      Sound like a plugged catalytic converter. That would also be the cause of your EGR valve code.

    • Guest - gopinathan

      Sir, I own a Matiz 1999 model.My mechanic carried out engine reboring after observing heavy smoke through exhaust pipe. After reboring, the engine starts normally, but when we accelerate the engine, the fuel flow is getting chocked and the engine is not picking up .

    • Guest - Tech

      In reply to: Guest - gopinathan

      Hard to say. But sounds like your mechanic did not do something correctly. Timing could be off, bore too large, rings not seating, etc.

    Latest Articles

    2014 Chevy Cruze Diesel for ...

    It's been a little over a year and a half since General Motors first confirmed plans to offer a ...

    Joe Flacco Wins New Corvette ...

    Super Bowl XLVII MVP Takes Home Chevrolet Corvette StingrayPresented by local Chevrolet dealer who ...

    New GM recalls 2012 cars over ...

    Report Receipt Date: JAN 24, 2013NHTSA Campaign Number: 13V023000Component(s): AIR BAGSVehicle ...

    GM Recalls Chevy Express And ...

    Summary:General Motors (GM) is recalling certain model year 2013 Chevy Express and GMC ...

    Login Or Register

    Log In Or Register
    ? The Benefits

    How Things Work

    Brakes- Front Disc- How Do They Work

    The disc brake system consists of the following components:

    Disc Brake Pads: Applies mechanical output force from the hydraulic brake calipers to friction surfaces of brake rotors.

    Disc Brake Rotors: Uses mechanical output force applied to friction surfaces from the disc brake pads to slow speed of tire and wheel assembly rotation.


    Common Engine Codes

    Oxygen Sensor Code P0036 and P0056

    P0036 - P0056
    Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature.