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DTC P0068

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0068 00: Throttle Body Air Flow Performance

Circuit/System Description

The engine control module (ECM) uses the following information to calculate an expected airflow rate:

    • The throttle position
    • The barometric pressure (BARO)
    • The intake air temperature (IAT)
    • The engine speed
    • The manifold absolute pressure (MAP)

Conditions for Running the DTC
    • DTCs P0106 00, P0107 00, P0108 00, and P0112 00 are not set.
    • The engine is running.
    • 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
    • DTCs P0068 00 is a Type A DTC.
    • The control module commands the throttle actuator control system to operate in the reduced engine power mode
    • A message centre or an indicator displays reduced engine power.
    • Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the DTC

DTC P0068 00 is a Type A DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Note: In extreme cold weather conditions ice may form in the vacuum source to the MAP sensor and may set a DTC. Inspect the MAP sensor and the vacuum source for ice, moisture, or other restrictions.

  1. Ignition ON, observe the MAP sensor pressure parameter and compare the reading on the scan tool to the barometric pressure table.
    2. ⇒If the MAP sensor pressure is not within the range specified for your altitude, refer toDTC P0106, P0107, or P0108 .
  2. Engine running, observe the MAP Sensor parameter. The reading should be between 32-42 kPa (4.6-6.0 PSI).
  3. 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.

Circuit/System Testing
  1. Verify none of the following conditions exist:
    2. • Vacuum hoses for splits, kinks, and proper connections
    • 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
    • Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust .
    • Air leaks at throttle body mounting area and intake manifold sealing surfaces
  2. 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.

    •  Throttle Body Assembly Replacement
    •  Air Cleaner Inlet Duct Replacement
    • Control Module References for ECM replacement, setup and programming
   


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