Circuit Description
The mass air flow (MAF) sensor measures the amount of air that is ingested by the engine. The MAF output voltage is a function of the power required to keep the sensing elements at a fixed temperature above ambient temperature as incoming air cools the sensing elements. The ECM calculates a mass air flow based on engine speed and throttle valve position. This value is continously compared to the reading from the MAF. This code will set if the calculation and actual values are not in agreement.
DTC Parameters
DTC P0101 will set when the following conditions exist:
| • | Deviation between TP signals is less than 0.6%. |
| • | No TP codes are set. |
When this code is set, the ECM will calculate the air flow from the other sensor inputs.
P0101 is a (type B) DTC.
Diagnostic Aids
Check for a stuck throttle plate. Observe the throttle angle with the throttle closed. If the reading is not within the typical scan tool values, check for faults in the TP sensor circuit.
Make sure MAF reads 0.0 g/s with engine Off.
Possible causes:
| • | Vacuum leaks |
| • | Air induction tubing loose or cracked |
| • | Corrosion in MAF sensor harness connector |
| • | Throttle plate stuck or carbon buildup |
| • | MAF sensor |
