For 1990-2009 cars only
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P2279: Intake Manifold Air LeakCircuit/System Description
The engine control module (ECM) compares actual vacuum reading of the manifold absolute pressure (MAP) sensor at idle to a calculated vacuum reading.
Conditions for Running the DTC
| • | DTCs P0106, P0107, P0108, P0112, P0113, P0115, P0117, P0118, P0122, P0123, P0125, P0128, P0131, P0132, P0133, P0134, P0135, P0141, P0171, P0172, P0201-P0204, P0217, P0300, P0336, P0337, P0341, P0342, P0351, P0352, P0402, P0404, P0405, P0406, P0488, P0496, P0502, P2195, and P2196 are not set. |
| • | The evaporative emission (EVAP) purge canister commanded state is less than 100 percent. |
| • | The barometric pressure (BARO) is greater than 72 kPa. |
| • | The engine coolant temperature (ECT) is greater than 60°C (140°F). |
| • | The intake air temperature (IAT) sensor is greater than -20°C (-4°F). |
| • | The manifold absolute pressure (MAP) is less than 60 kPa. |
| • | The engine is operating for greater than 60 seconds. |
| • | The engine is at idle with the throttle closed. |
| • | The ECM is not commanding an IAC motor reset. |
| • | The following components are not changing states: |
| - | The A/C compressor |
| - | The engine cooling fans |
| - | The automatic transmission |
| • | The DTC runs continuously when the above conditions are met for 5 seconds. |
Conditions for Setting the DTC
| • | The ECM detects that the predicted intake air flow into the engine is not within a predetermined range of the actual air flow into the engine. |
| • | The condition exists for greater than 20 seconds. |
Action Taken When the DTC Sets
DTC P2279 is a Type B DTC.
Conditions for Clearing the DTC
DTC P2279 is a Type B DTC.
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, observe the DTC information with a scan tool. DTC P2279 should not set.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
- Verify none of the following conditions exist:
- If all conditions test normal, test the engine for proper camshaft timing. Refer to Timing Belt Replacement.
| • | The air intake duct system for loose connecting clamps, cracks, or other damage |
| • | A damaged throttle body blade or shaft |
| • | Splits, kinks, or improper connections at the vacuum hoses |
| • | An exhaust gas recirculation (EGR) system leak |
| • | Faulty positive crankcase ventilation (PCV) system operation |
| • | Carbon deposits on the throttle blade--Refer to Throttle Body Inspection and Cleaning. |
| • | Vacuum leaks at the intake manifold, throttle body, and injector O-rings |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
