Description
The engine control module (ECM) tests for a misalignment between both camshafts on one bank of the engine and the crankshaft. The mis-alignment would be at an idler sprocket for bank 1 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. If the ECM detects both learned values for one bank of the engine is exceeding a calibrated threshold in the same direction, this DTC sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0008 Engine Position System Performance Bank 1
Conditions for Running the DTC
| • | DTCs 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, and P2095 are not set. |
| • | The engine is running for more than 50 seconds. |
| • | The engine coolant temperature is between 0-95°C (32-203°F). |
| • | The calculated engine oil temperature is less than 120°C (248°F). |
| • | DTC P0008 runs continuously once the above conditions 2 ignition cycles are met. |
Conditions for Setting the DTC
The ECM detects that both camshafts on bank 1 of the engine are mis-aligned with the crankshaft for more than 4 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 4 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
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). |
| • | Observing the desired and actual camshaft angle parameters, with a scan tool before a DTC sets, may help to isolate whether a condition is specific to one camshaft, one bank, or caused by a condition with the primary crankshaft timing. |
| • | For an intermittent condition, refer to Intermittent Conditions . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Did the DTC fail this ignition? | Go to Step 4 | Go to Step 3 |
3 |
Did the DTC fail this ignition? | Go to Step 4 | Go to Diagnostic Aids |
4 | Inspect the timing chains and tensioners for excessive wear or misalignment. Refer to Camshaft Timing Drive Chain Alignment Diagram and Camshaft Timing Drive Components Cleaning and Inspection . Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
Inspect the crankshaft reluctor wheel for being mispositioned on the crankshaft. Refer to Crankshaft and Bearing Cleaning and Inspection . Did you complete the repair? | Go to Step 6 | -- | |
6 |
Did the DTC fail this ignition? | Go to Step 2 | Go to Step 7 |
7 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK |
