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P2281






P2281-AIR LEAK BETWEEN MAF AND THROTTLE BODY

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation
This monitor can detect a large leak located anywhere between the Turbocharger outlet and the Intake Manifold. The monitor compares the estimated EGR flow to the actual EGR flow. If the actual EGR flow is much less than the estimated EGR flow, the fault will set. If the CAC hose is leaking or disconnected, the Turbocharger can still have enough exhaust flow that the compressor will draw air through the MAF. Charge Flow will be low since the flow is not reaching the Intake Manifold. This will cause the fault to be set.
- When Monitored:
Continuously with engine running.

- Set Condition:
The Powertrain Control Module (PCM) detects that the actual EGR flow is less than the estimated EGR flow by a calibrated value.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. VISUAL INSPECTION
1. Turn ignition off.
2. Perform a visual inspection of the Intake system for disconnected hoses or loose hose clamps between the Turbocharger and the Intake Manifold.

Were any disconnected hoses or loose clamps found?

Yes

- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 2

2. CHECK THE INTAKE SYSTEM
1. Perform the INTAKE AIR SYSTEM PRESSURE TEST diagnostic procedure. . Intake Air System Pressure Test

Were any leaks found?

Yes

- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Perform the INTERMITTENT CONDITION - 6.7L diagnostic procedure. . Intermittent Condition Test