DC13 - Air Leak at MAF Sensor

Engine Running Diagnostic Trouble Code (DTC) 129 indicates insufficient Mass Air Flow Sensor (MAF) change during Dynamic Response Test.

Possible causes:

- Open MAF circuit.

- Open VPWR circuit to MAF sensor.

- Open PWR GND circuit to MAF sensor.

- Open MAF RTN circuit to MAF sensor.

- MAF circuit shorted to ground.

- Damaged Powertrain Control Module (PCM).

- Damaged MAF sensor.

- Air leak before or after MAF sensor.

- MAF sensor disconnected.

- Idle Air Control (IAC) system failure (at closed throttle position).

- Check for broken/loose air outlet tube clamps (throttle body and air cleaner assembly ends), cracks/holes in air outlet tube, worn gaskets between MAF sensor and air cleaner assembly.

- Is a fault indicated?

Yes -- Service as necessary. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Go to DC14. DC14 - Check Continuity of MAF and VPWR Circuits