P0018: Crankshaft-Camshaft Correlation Bank 2 Sensor A
The P0018 code indicates that the engine control module (ECM) has detected a misalignment between the crankshaft and the camshaft on bank 2, sensor A (typically the intake camshaft). This correlation error means the camshaft timing is not synchronized with the crankshaft position, often due to a stretched timing chain, failed variable valve timing (VVT) actuator, or oil flow issues. Bank 2 refers to the cylinder bank opposite cylinder #1 (usually the passenger side on V6/V8 engines).
1. Most Common Causes
- Timing chain or belt stretched, damaged, or jumped out of position
- Faulty timing chain/belt tensioner or guide
- Bank 1 camshaft position (CMP) sensor damaged or contaminated
- Crankshaft position (CKP) sensor damaged
- CMP or CKP sensor wiring open or shorted
- Poor electrical connections or corrosion at sensor connectors
- Damaged or misaligned reluctor wheel for CKP or CMP sensor
- Degraded engine oil or low oil level (affecting variable valve timing actuator if applicable)
2. Symptoms You Will Notice
- Check Engine Light on
- Rough idle or engine misfire
- Reduced engine power and fuel economy
- Engine may run poorly or stall
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Check engine oil level and condition; inspect for contamination.
Step 3: Visually inspect timing chain/belt and VVT components for wear or damage.
Step 4: Test VVT solenoid operation with a multimeter or scan tool.
Step 5: Perform a correlation test using a scan tool to compare crankshaft and camshaft positions.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with P0018 can cause poor engine performance, increased emissions, and potential internal engine damage if the timing is severely off.
How much does it cost to fix?▼
Repair costs vary widely: $200-$400 for a VVT solenoid replacement, $500-$800 for timing chain replacement, plus diagnostic fees.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.