Code 33 (MFI CALIF. & New YORK) - Mass Airflow Sensor High Current Input: Notes

MAF sensor measures the amount of air which passes through it in a given amount of time. ECM controls fuel delivery by using this information to determine the operating condition of the engine. A large quantity of air movement indicates acceleration, while a small quantity indicates deceleration or idle. As amount of air entering sensor increases, sensor signal current to ECM also increases. As airflow decreases, sensor signal current to ECM decreases. MAF sensor is located between air intake tube and air cleaner in left front of engine compartment. Code 33 will set MAF sensor output current is higher than 4.9 milliamps for more than 100 milliseconds.

1. Checks for a faulty MAF sensor circuit without engine running.
2. Checks for a faulty MAF sensor or ECM.
3. Checks for open in Black wire between MAF sensor and G110.
4. Checks for a faulty MAF sensor or ECM, and a short to voltage in Gray/Black wire between ECM and MAF sensor.