DTC P0068 or P1101
Diagnostic Instructions
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 greater than 800 RPM. |
• | The ignition voltage is greater than 6.0 V. |
• | The throttle actuator control system is not in reduced power mode. |
• | The DTC runs continuously when the above conditions are met. |
DTC P1101
• | DTCsP0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0335, P0336 are not set |
• | The engine speed is between 400-7,000 RPM |
• | The engine coolant temperature (ECT) is between 69-127°C (156-260°F). |
• | The inlet 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 DTC
The ECM detects that the actual airflow rate is greater than the calculated airflow.
Action Taken When the DTC Sets
• | DTC P0068 is a type A DTC. |
• | DTC P1101 is a type B DTC. |
Conditions for Clearing the DTC
• | DTC P0068 is a type A DTC. |
• | DTC P1101 is a type B DTC. |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
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 Testing
- Verify none of the following conditions exist:
• | The air inlet duct system for loose clamps, cracks, or other damage |
• | The air inlet duct system for being collapsed or restricted |
• | The B75 mass airflow sensor is installed correctly. |
• | Splits, kinks, or improper connections at the vacuum hoses |
• | Vacuum leaks at the intake manifold and Q38 throttle body. |
⇒ | If a condition exists, repair as necessary. |
- Ignition ON, observe the diagnostic trouble code (DTC) information with a scan tool. Verify that DTC P0641, P0651, P0697, or P06A3 is not set.
- Determine the current vehicle testing altitude. Compare the MAP Sensor pressure parameter to the reading in the Altitude Versus Barometric Pressure table. The MAP sensor pressure parameter should be within the specified range indicated in the table.
- Engine idling, observe the MAP Sensor kPa parameter. The reading should be between 26-52 kPa (3.8-7.5 psi).
- Use the scan tool snapshot function to take a snapshot of the engine data list while performing the actions listed below.
5.2. | Increase the engine speed slowly to 3,000 RPM and then back to idle. |
5.3. | Exit from the scan tool snapshot and review the data. |
5.4. | Observe the MAF Sensor g/s parameter frame by frame with a scan tool. The MAF Sensor g/s parameter should change smoothly and gradually as the engine speed is increased and then returned to idle. |
- If all conditions test normal, test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical .
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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