Circuit/System Verification

Verify that the following DTCs are not set: P0641 or P0651.
- If any of the DTCs are set, refer to DTC P0641 or P0651
Verify restrictions do not exist in the exhaust system-Refer to Restricted Exhaust .
Ignition ON, observe the MAP Sensor and SC Inlet Pressure Sensor kPa parameters with a scan tool. Start the engine and let it idle. The MAP and SC Inlet Pressure Sensor kPa parameters should decrease and closely match each other.
- If the MAP Sensor kPa parameter does not decrease and closely match each other, refer to DTC P0106 .
- If the SC Inlet Pressure kPa parameter does not decrease and closely match each other, refer to DTC P012B .
Ignition ON, depress the accelerator pedal completely to wide open throttle (WOT) and observe the TP Indicated Angle parameter with a scan tool. The TP Indicated Angle parameter should read 98-100 percent.
- If the TP Indicated Angle parameter is not within the specified range, refer to DTC P1516, P2101, P2119, or P2176 .
Ignition ON, engine OFF, perform a snapshot of the throttle actuator control (TAC) data while performing the following actions. Refer to Scan Tool Snapshot Procedure .
1. Slowly depress the accelerator pedal to WOT position and then slowly release the pedal. Exit from the snapshot and review the data.
2. Compare the TP Sensor 1 Indicated Position and the TP Sensor 2 Indicated Position parameters, frame by frame. The difference between the values should be less than 4 percent.
- If the difference is greater than 4 percent, refer to DTC P0120, P0122, P0123, P0220, P0222, P0223, or P2135 .
Road the vehicle and perform a brief wide open throttle (WOT) acceleration from 30 mph. The MAP sensor parameter on the scan tool should increase rapidly. This increase should be from approximately 35 kPa at idle to greater than 135 kPa.
- If the MAP Sensor parameter does not increase to greater than the specified range, refer to Boost Control System Diagnosis .
Road test the vehicle and verify that the MAF sensor calculated g/s and the actual MAF g/s parameters are near or equal to each other.
A skewed or stuck ECT, BARO, MAP, MAF/IAT, or IAT sensor 2 will cause the calculated models to be inaccurate and may cause this DTC to run when it should not. Refer to Temperature Versus Resistance andAltitude Versus Barometric Pressure .
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.