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How do I fix P0101: Mass or Volume Air Flow Circuit Range/Performance?

Discussion in 'Gen 2 Prius Main Forum' started by MilkyWay, Aug 22, 2016.

  1. MilkyWay

    MilkyWay Active Member

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    Engine light came on today and this is the code: P0101.

    What is the fix or possible fixes? Thanks
     
  2. ILuvMyPriusToo

    ILuvMyPriusToo Senior Member

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    Probably the MAF sensor needs to be cleaned (carefully) or replaced.
     
  3. MilkyWay

    MilkyWay Active Member

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    I pulled it off, sprayed it, let dry and put back on...will update if code pops back on
     
  4. calin.ceascai

    calin.ceascai Junior Member

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    Hi. Please give me some details. Which is MAF sensor? I have same problem P0101. Thanks.

    Trimis de pe Huawei P10 Leica folosind Tapatalk
     
  5. MilkyWay

    MilkyWay Active Member

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    It requires a very tiny screw driver....Here is location and the video I used....

    Capture.PNG



     
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  6. calin.ceascai

    calin.ceascai Junior Member

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    Thanks for your kind answer.

    Trimis de pe Huawei P10 Leica folosind Tapatalk
     
  7. Mendel Leisk

    Mendel Leisk Senior Member

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    Probably noted in the videos, but: there's a very specific cleaner to use: Mass Air Flow Sensor Cleaner (aka MAF Sensor Cleaner). It's readily available in North America, by CRC for one.

    You're in Romania, Rome, or?? (n)
     
  8. Dxta

    Dxta Senior Member

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    Solving this problem is quite easy.

    First things first.

    Remove the MAF if you can, and inspect it for dirty. If you've got dirt's stuck in the thermistor of the MAF sensor, it sends a weird kind of signals to the car's ECU, and in term, you might get misfire issues, and excess fuel consumptions.

    Secondly, do a voltage test(I mean check if you've got power being fed to the sensor from the ECU wiring harness. If you're not getting, 12volts(I can't remember the specified voltage input), the sensor would send wrong signals.

    Thirdly, do a ground test, to confirm if the circuit is complete. If it isn't, you've got problem in your hands.

    Fourthly, and the most important, is to do a signal voltage test. In this test, the MAF, monitors and measures the amount of incoming ambient air, and converts this signal(m/g) to a 5volt signal, which it sends to the ECU, for proper metering of the fuel system.

    Fifth, would be a last resort, if after you've done all the aforementioned tests, and the situation still persists, the ECU or the MAF sensor wiring harness to the ECU might be the culprit.

    Do relay to the house your findings pls.

    PS: The FFD is very important in troubleshooting this.

    Dxta
     
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  9. calin.ceascai

    calin.ceascai Junior Member

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    Thanks a lot.

    Trimis de pe Huawei P10 Leica folosind Tapatalk
     
  10. calin.ceascai

    calin.ceascai Junior Member

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    Romania.

    Trimis de pe Huawei P10 Leica folosind Tapatalk
     
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  11. Cactuscoug

    Cactuscoug CactusCoug

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    I had the same P0101 on my 2011 Prius. Taking my cue from this forum, I cleaned the MAF, twice. I cleaned the throttle body. I reset the codes. They returned. After a couple of months of this, I took my Prius into a local repair shop. Fuel Pump!! $950 later, I was repaired. A side benefit, is that the indicated fuel mileage was repaired as well. It had been reading 40mpg when I was actually getting 50mpg. I guess the sensor in the fuel pump thought it was moving more fuel than it actually was.
     
  12. prius_nerd

    prius_nerd Junior Member

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