Important: The following applies to the intake airflow system performance diagnostic that is used in this supercharged engine:

The intake airflow system performance diagnostic provides the within-range rationality check for the mass air flow (MAF), supercharger inlet absolute pressure (SCIAP), MAP, by-pass valve stuck, and the throttle position (TP) sensors. This is an explicit model-based diagnostic containing 4 separate models for the intake system.

The estimates of MAF, SCIAP, and TP that are obtained from this system of models and calculations are then compared to the actual measured values from the MAF, SCIAP, and the TP sensors and to each other to determine the appropriate DTC to fail. The following table illustrates the possible failure combinations and the resulting DTC or DTCs.

DTC P0106 is a Type B DTC.

DTC P0106 is a Type B DTC.

Caution: Refer to Road Test Caution in the Preface section.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Special Tools Required

1. Verify that DTCs P0641 and P0651 are not set.

⇒	If any of the DTCs are set, refer to DTC P0641 or P0651 .

2. Verify that restrictions do not exist in the exhaust system. Refer to Restricted Exhaust .
3. Verify that the engine is in good mechanical condition. Refer to Symptoms - Engine Mechanical for the 4.4L engine.
4. Ignition ON, observe the scan tool MAP, SC Inlet Pressure, and BARO parameters. Verify the MAP, SC Inlet Pressure, and BARO sensor parameters are within 5 kPa of each other.
5. Ignition ON, observe the MAP Sensor kPa parameter with a scan tool. Start the engine. The MAP Sensor kPa parameter should change.
6. Engine running at idle, observe and record the MAP Sensor parameter kPa value with a scan tool. Slowly increase the engine speed from idle to 2,000 RPM, then allow the engine speed to return idle. The MAP sensor parameter should increment to a higher value at 2,000 RPM and return to the recorded idle value.
7. Ignition ON, compare APP sensors 1 and 2 percentages with a scan tool. Verify that they do not differ more than 5 percent while performing a slow pedal sweep is performed.
8. Ignition ON, observe the scan tool MAP sensor parameter. Start the engine. The MAP Sensor parameter should change.
9. Engine running, observe the DTC information with a scan tool. DTCs P0106 should not set.
10. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Verify the integrity of the entire supercharger air induction system by inspecting for the following conditions:

•	Damaged components

•	Loose or improper installation

•	An air flow restriction

•	Any vacuum leak

•	Improperly routed vacuum hoses

•	In cold climates, inspect for any snow or ice buildup.

•	Verify that restrictions do not exist in the MAP sensor port or vacuum source.

2. Ignition OFF, disconnect the harness connector at the MAP sensor.
3. Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference circuit terminal A and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.

⇒	If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

⇒	If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

5. Verify the scan tool MAP parameter is less than 15 kPa.

⇒	If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the ECM.

6. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference terminal C. Verify the scan tool MAP parameter is greater than 200 kPa.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

7. If all circuits test normal, test or replace the MAP sensor.

Important: You must perform the Circuit/System Testing in order to verify the integrity of the MAP sensor circuits before proceeding with the Component Testing.

1. Ignition OFF, remove the MAP sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal C and the corresponding terminal of the MAP sensor.
3. Install a jumper wire between the low reference circuit terminal A of the MAP sensor and ground.
4. Install a jumper wire at terminal B of the MAP sensor.
5. Connect a DMM between the jumper wire from terminal B of the MAP sensor and ground.
6. Ignition ON, with the J 23738-A or J 35555 , slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 4.9-0.04 volts, without any spikes or dropouts.

⇒	If the voltage reading is erratic, replace the MAP sensor.

1. Ignition ON, observe the MAP, SC Inlet Pressure, and BARO parameters with a scan tool. The MAP, SC Inlet Pressure, and BARO sensor parameters should be within 5 kPa of each other.
2. With a scan tool, command the supercharger bypass control valve ON. Slowly increase the engine speed from idle to 2,000 RPM and return the engine to idle speed. The MAP sensor parameter should increment to a higher value and return to the normal idle value.