Possible causes

– Air leak between the MAF sensor and throttle body
– Dirty Throttle body or Mass Air Flow (MAF) sensor
– Throttle Position (TP) sensor not seated properly
– Faulty Throttle Position (TP) sensor
– Faulty Mass Air Flow (MAF) sensor

When is the code detected?

If the PCM detects that the difference between the actual air flow (MAF) and the speed density calculated air flow is greater than expected, DTC P0068 sets.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/Loss of power
– Engine rough idle

P0068 CHEVROLET Description

The Powertrain Control Module (PCM) uses the Throttle Position (TP), Barometric Pressure (BARO), Intake Air Temperature (IAT), and engine RPM in order to calculate the predicted mass airflow rate. The PCM compares the predicted Mass Air Flow (MAF) value to the actual mass airflow value and the speed density calculation in order to verify the proper throttle operation.

CHEVROLET Technical Service Bulletins for P0068 code