Cylinder #4 Imbalance Error
The P219F code indicates that the engine control module (ECM) has detected an imbalance in cylinder #4's air-fuel mixture compared to the other cylinders. This typically means cylinder #4 is running leaner or richer than expected, which can cause rough idling, misfires, and reduced fuel efficiency. Common causes include vacuum leaks, fuel injector issues, ignition problems, or mechanical engine faults.
1. Most Common Causes
- Vacuum leak near cylinder #4
- Faulty fuel injector on cylinder #4
- Ignition coil or spark plug issue on cylinder #4
- Low compression in cylinder #4
2. Symptoms You Will Notice
- Rough idle or engine vibration
- Check Engine Light illuminated
- Decreased fuel economy
- Engine misfire or hesitation
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Inspect vacuum hoses and intake manifold gasket for leaks near cylinder #4.
Step 3: Swap ignition coil and spark plug from cylinder #4 to another cylinder and see if the code follows.
Step 4: Perform a fuel injector balance test or swap injectors to isolate the issue.
Step 5: Check compression on cylinder #4 to rule out mechanical problems.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the imbalance can cause catalytic converter damage and poor engine performance. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The cost varies depending on the cause. A simple vacuum leak repair may cost $50-$150, while replacing a fuel injector or ignition coil can range from $150-$400.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.