For 1990-2009 cars

### 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 P0016: Crankshaft Position (CKP) - Intake Camshaft Position (CMP) Correlation Bank 1
DTC P0017: Crankshaft Position (CKP) - Exhaust Camshaft Position (CMP) Correlation Bank 1
DTC P0018: Crankshaft Position (CKP) - Intake Camshaft Position (CMP) Correlation Bank 2
DTC P0019: Crankshaft Position (CKP) - Exhaust Camshaft Position (CMP) Correlation Bank 2

### Circuit/System Description

The camshaft position (CMP) actuator system enables the engine control module (ECM) to change the timing of the camshafts while the engine is operating. The ECM sends an electrical signal to the CMP actuator solenoids through the control circuits when a camshaft timing change is desired. The low reference circuit is used as a return. The CMP actuator solenoid uses electromagnetic force to pull on the plunger of the oil control valve. The oil control valve will port the pressurized engine oil to either the advancing or retarding chambers of the CMP actuator. The CMP actuator changes the camshaft position relative to the crankshaft position. If the ECM detects the difference between the desired camshaft position, and the actual camshaft position angle is greater than the specified value, DTC P0016, P0017, P0018, or P0019 will be set.

### Conditions for Running the DTC

• | DTCs P0010, P0011, P0013, P0014, P0020, P0021, P0023, P0024, P0335, P0336, P0340, P0341, P0345, P0346, P0365, P0366, P0390, P0391, P2088, P2089, P2090, P2091, P2092, P2093, P2094, P2095 are not set.

• | The engine speed is less than 1,200 RPM.

• | The crankshaft position signal is within the specifications.

• | The camshaft is at the default position.

• | DTC P0016, P0017, P0018, or P0019 runs continuously when the above conditions are met.

### Conditions for Setting the DTC

The ECM detected the CMP dropping signal relative to the CKP dropping signal without -10 to +11 degrees, and it occurs 25 times during 35 tests.

### Action Taken When the DTC Sets

DTCs P0016, P0017, P0018 or P0019 are Type B DTCs.

### Conditions for Clearing the DTC

DTCs P0016, P0017, P0018 or P0019 are Type B DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

• | Engine Control Module Connector End Views

• | Engine Controls Connector End Views

#### Description and Operation

• | Camshaft Actuator System Description

• | Electronic Ignition (EI) System Description

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

• | Scan Tool Data List

• | Scan Tool Data Definitions

• | Engine Control Module Scan Tool Information

### Circuit/System Verification

Important: The supply of clean pressurized engine oil to the CMP actuator is essential to CMP actuator performance.

1. Observe the engine oil level. The engine oil level should be within the operating range. Refer to Fluid Capacity - Approximate.
2. Ensure that the vehicle has the correct engine oil and is not old, burnt, or contains additives. Refer to Checking Things Under the Hood in Service and Appearance Care within the Owner's Manual.

⇒ | If the vehicle has the incorrect engine oil, is old, burnt, or contains additives, change the oil and filter.

3. Test the engine oil pressure for correct operation. Refer to Oil Pressure Diagnosis and Testing .
4. Allow the engine to reach operating temperature.
5. Apply the parking brake and shift the vehicle in Park for automatic, or Neutral for manual.
6. Observe the CMP Variance parameter. The CMP Variance will rise within 1-2 seconds until the CMP Angle value matches the Desired CMP value. The CMP Variance value should return to 0 degree once again.

Important: The engine will run rough and may require throttle input to keep it continuously running.

7. Command the CMP actuator to 20 degrees. The Desired CMP parameter should match the CMP Angle parameter.

### Circuit/System Testing

• | Inspect the engine or review the service history of the vehicle for any recent repairs involving the timing chain, camshaft, or crankshaft.

⇒ | If recent repairs were made, refer to Camshaft Timing Drive Chain Alignment Diagram and inspect the timing chain and sprockets for proper alignment.

• | Inspect the CMP actuator. Refer to Camshaft Position Actuator Housing Cleaning and Inspection .

• | Inspect the engine timing components. Refer to Camshaft Timing Drive Components Cleaning and Inspection .

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.