GM Service Manual Online
For 1990-2009 cars only

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 Descriptors

DTC P0008: Engine Position System Performance Bank 1

DTC P0009: Engine Position System Performance Bank 2

Circuit/System Description

The engine control module (ECM) tests for a misalignment between both camshafts on one bank of the engine and the crankshaft. The misalignment would be at an idler sprocket for either bank or at the crankshaft. Once the ECM learns the position of both camshafts on one bank of the engine, the ECM compares the learned values to a reference value. The ECM will set a DTC if both learned values for one bank of the engine are exceeding a calibrated threshold in the same direction.

Conditions for Running the DTC

    • DTC P0010, P0011, P0013, P0014, P0020, P0021, P0023, P0024, P0341, P0342, P0343, P0346, P0347, P0348, P0366, P0367, P0368, P0391, P0392, P0393, P2088, P2089, P2090, P2091, P2092, P2093, P2094, or P2095 is not set.
    •  The engine is operating for greater than 50 seconds.
    • The engine coolant temperature is between 0-95°C (32-203°F).
    • The calculated engine oil temperature is colder than 120°C (248°F).
    •  The engine must accelerate such that the CMP actuator system is commanded from the park position to the phased position. This is considered a cam control cycle. There must be a minimum of 2 cam control cycles for at least 2.5 seconds each, in the phased position.
    • DTC P0008 and P0009 run continuously once the above conditions are met, approximately 600 seconds.

Conditions for Setting the DTC

The ECM detects that both camshafts on either bank of the engine are mis-aligned with the crankshaft, greater than 6 degrees, for greater than 4 seconds or a cumulative of 30 seconds.

Action Taken When the DTC Sets

DTC P0008 and P0009 are type B DTCs.

Conditions for Clearing the DTC

DTC P0008 and P0009 are type B DTCs.

Diagnostic Aids

    • Inspect the engine for any recent engine mechanical repairs. An incorrectly installed secondary timing chain can cause this DTC to set.
    •  A single failed camshaft actuator or actuator solenoid will not cause this DTC to set. This diagnostic algorithm is designed to detect an alignment condition between a primary intermediate sprocket and the secondary timing chain, or the alignment between a primary intermediate sprocket and the crankshaft. Either condition would cause the camshaft timing for both cams on one bank to be off an equal number of degrees.
    • The presence of DTCs P0008 and P0009 along with P0016, P0017, P0018, and P0019 indicates a possible condition with the primary timing chain and the alignment between both intermediate sprockets and the crankshaft. Or, the crankshaft reluctor wheel has moved and is no longer referenced to top dead center (TDC).
    • Observe the scan tool CMP Desired, Actual, and Angle Variance parameters before a DTC sets. This may help to isolate whether a condition is specific to one camshaft, one bank, or caused by a condition with the primary crankshaft timing.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Clear the DTCs with a scan tool.
  2. Allow the engine to reach the normal operating temperature.
  3. Idle the engine for 10 minutes or until a DTC sets. Observe the DTC information with a scan tool, DTCs P0008 and P0009 should not set.
  4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

  1. Inspect the timing chains and tensioners for excessive wear or misalignment.
  2. If you find a condition with the timing chains or tensioners, repair as necessary.
  3. Inspect the crankshaft reluctor wheel for being mis-positioned on the crankshaft.
  4. If you find a condition with the crankshaft, repair as necessary.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Setting Camshaft Timing
    •  Camshaft Timing Drive Chain Alignment Diagram
    •  Camshaft Timing Drive Components Cleaning and Inspection
    •  Crankshaft and Bearing Cleaning and Inspection