DTC Advanced Diagnostics: P0101
DTC P0101:Mass Airflow (MAF) Sensor Circuit Range/Performance Problem (Engine Type: J35Y1, J35Y2)

General Description
The mass airflow (MAF) sensor directly measures the amount of intake airflow into the engine, and the powertrain control module (PCM) controls the fuel injection based on the measured value. The manifold absolute pressure (MAP) sensor measures the intake manifold pressure, and the PCM calculates the amount of intake airflow from the MAP sensor output and the engine revolutions. The PCM compares the MAF sensor output (amount of intake airflow) and the amount of intake airflow calculated from MAP sensor output. If their difference is too large (in the malfunction area), the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Execution
Once per driving cycle
Sequence
None
Duration
5.0 seconds or more
DTC Type
Two drive cycles, MIL on
OBD Status
PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Enable Conditions
Condition
Minimum
Maximum
Elapsed time after starting the engine
3.0 seconds
–
Engine coolant temperature
[ECT SENSOR 1]
156 °F (69 °C)
–
Engine speed
[ENGINE SPEED]
A/T model
550 rpm
6,900 rpm
M/T model
650 rpm
6,900 rpm
No active DTCs set (prevents monitor from running)*1
P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0171, P0172, P0174, P0175, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0335, P0339, P0351, P0352, P0353, P0354, P0355, P0356, P0401, P0404, P0443, P0496, P0497, P0506, P0507, P1128, P1129, P145C, P2279, P2413, P2646, P2647, P2648, P2649, P2652, P2654, P2656, P2657, P2658, P2659,
No active DTCs set (prevents monitor from running)*2
P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0335, P0339, P0351, P0352, P0353, P0354, P0355, P0356, P0401, P0404, P0443, P0506, P0507, P2279, P2413, P2646, P2647, P2648, P2649, P2652, P2654, P2656, P2657, P2658, P2659,
*1: 2013, 2014, 2015 models

*2: 2016 model on and after

[ ]: HDS Parameter

Malfunction Threshold
The difference between the amount of intake air measured by the MAF sensor and the amount of intake air calculated from the MAP sensor output is out of the normal area for at least 5.0 seconds.

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
Intake air duct loose connection or misinstalled
Intake air duct damage
Evaporative emission (EVAP) canister purge hose misinstalled
Intake manifold damage
MAP sensor misinstalled
Positive crankcase ventilation (PCV) hose misinstalled
Air cleaner element damage
Air cleaner element clogged
MAF sensor element damage

Confirmation Procedure
Operating Condition

1.
Start the engine. Hold the engine speed [ENGINE SPEED] at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on.
2.
Let the engine idle for at least 5 seconds.
3.
Drive the vehicle at a steady speed of 40 mph (64 km/h) or more for at least 5 seconds.
When freeze data is stored, drive the vehicle under those conditions instead of Driving Pattern step 3.
When you have difficulty duplicating the DTC because of road conditions and traffic situations, repeat the driving pattern several times.
Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
With the HDS
None.

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.