P0068

DTC P0068

DTC Descriptor
DTC P0068
- Throttle Body Airflow Performance

Diagnostic Fault Information

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

Circuit/System Description

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

Conditions for Running the DTC

* The engine is running.
* DTCs P0106, P0107, P0108, P0110, P0111, and P0112 are not set.
* The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

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

Action Taken When the DTC Sets

DTC P0068 is a Type A DTC.

Conditions for Clearing the DTC

DTC P0068 is a Type A DTC.

Reference Information

Schematic Reference

Engine Controls Schematics Electrical Diagrams

Connector End View Reference
* Engine Control Module (ECM) Connector End Views Engine Control Module (ECM) Connector End Views
* Engine Controls Connector End Views Engine Controls Connector End Views

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

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

Scan Tool Reference
* Scan Tool Data List Scan Tool Data List
* Scan Tool Data Definitions Scan Tool Data Definitions
* Scan Tool Output Controls Scan Tool Output Controls

Circuit/System Verification

1. Ignition ON, observe the manifold absolute pressure (MAP) sensor pressure parameter and compare the reading on the scan tool to the barometric pressure table. Refer to Altitude vs Barometric Pressure Altitude vs Barometric Pressure.

• If the MAP sensor pressure is not within the range specified for your altitude, refer to DTC P0107 or P0108 P0107.

2. Start the engine, observe the MAP Sensor parameter. The reading should be between 32-42 kPa.
3. If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

1. Verify that none of the following conditions exist:

* The air intake duct system for loose connecting clamps, cracks, or other damage
* The air intake duct system for being collapsed or restricted possibly by a restricted air filter
* A damaged throttle body blade or shaft
* Splits, kinks, or improper connections at the vacuum hoses
* Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust Symptoms - Engine Exhaust.
* Vacuum leaks at the intake manifold, throttle body, and injector O-rings

2. If all conditions test normal, test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical Symptoms - Engine Mechanical.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification Diagnostic Repair Verification after completing the diagnostic procedure.


* Throttle Body Assembly Replacement Removal and Replacement
* Air Cleaner Assembly Replacement Service and Repair
* PSD SIE TITLE Error: SIE linked to empty Cell ID 125196