P0068

DTC P0068 or P1101

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0068
- Throttle Body Airflow Performance

DTC P1101
- Intake Air Flow System Performance

Circuit/System Description

The engine control module (ECM) compares actual airflow based on throttle position (TP) to a calculated airflow based on manifold absolute pressure (MAP) sensor, and mass air flow (MAF).

Conditions for Running the DTC

DTC P0068

* The engine speed is at least 800 RPM.

* The ignition voltage is at least 6.4 V.

* The DTC runs continuously when the above conditions are met.

DTC P1101

* DTC P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0116, P0117, P0118, P0128, P0335, or P0336 is not set

* The engine speed is between 575-6,600 RPM

* The engine coolant temperature (ECT) is between -7 to +125°C (+19 to +257°F).

* The intake air temperature (IAT) is between -20 to +125°C (-4 to +257°F).

* The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTCs

The ECM detects that the actual airflow rate is greater than the calculated airflow.

Action Taken When the DTCs Set

* DTC P0068 is a type A DTC.

* DTC P1101 is a type B DTC.

Conditions for Clearing the DTCs

* DTC P0068 is a type A DTC.

* DTC P1101 is a type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views Outside Rearview Mirror - Driver

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, verify that DTC DTC P0641, P0651, P0697, or P06A3 is not set.

• If none of the DTCs are set
Refer to DTC P0641, P0651, P0697, or P06A3 (ECM) Powertrain Management (ECM) for further diagnosis.

• If the DTC is not set

2. Ignition ON, verify the scan tool TB Idle Airflow Compensation parameter is less than 90 %.

• If 90% or greater
Refer to Throttle Body Cleaning Procedures.

• If less than 90%

3. Verify the scan tool Throttle Position Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Disagree
Refer to DTC P0641, P0651, P0697, or P06A3 (ECM) Powertrain Management (ECM) for further diagnosis.

• If Agree

4. Determine the current vehicle testing altitude.

5. Verify the scan tool MAP Sensor pressure parameter is within the range specified in the Altitude Versus Barometric Pressure Specifications table.

• If the MAP Sensor parameter is not in range
Refer to DTC P0106 P0106 for further diagnosis.

• If the MAP Sensor parameter is in range

6. Verify the scan tool Boost Pressure Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure Specifications table.

• If the Boost Pressure Sensor parameter is not in range
Refer to DTC P0236, P0237, or P0238 P0236 for further diagnosis.

• If the Boost Pressure Sensor parameter is in range

7. Verify the scan tool Boost Pressure Sensor parameter decreases after starting the engine.

• If the Boost Pressure Sensor parameter does not decrease
Refer to DTC P0236, P0237, or P0238 P0236 for further diagnosis.

• If the Boost Pressure Sensor parameter does decrease

8. Engine idling, verify the scan tool MAP Sensor pressure parameter is between 26-52 kPa (3.8-7.5 psi) and changes with accelerator pedal input.

• If not between 26-52 kPa (3.8-7.5 psi) or does not change
Refer to DTC P0106 P0106 for further diagnosis.

• If between 26-52 kPa (3.8-7.5 psi) and changes

9. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling

2. Perform the scan tool snapshot function.

3. Increase the engine speed slowly to 3,000 RPM and then back to idle.

4. Exit from the scan tool snapshot and review the data.

5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• If the MAF Sensor parameter does not change smoothly and gradually
DTC P0101 P0101 for further diagnosis.

• If the MAF Sensor parameter does change smoothly and gradually

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.

11. Verify a DTC does not set.

• If any DTC sets
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• If no DTCs set

12. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Air Cleaner Element Replacement Service and Repair

* Throttle Body Assembly Replacement Removal and Replacement

* Control Module References Control Module References for engine control module replacement, programming, and setup.