Cylinder #4 Imbalance Error
The P219F code indicates that the engine control module (ECM) has detected an imbalance in cylinder #4, meaning its air-fuel mixture is significantly different from the other cylinders. This can be caused by a vacuum leak, fuel injector issue, ignition problem, or mechanical fault within that cylinder. The imbalance can lead to rough idle, misfires, and reduced fuel economy.
01. Most Common Causes
- Vacuum leak near cylinder #4
- Faulty fuel injector on cylinder #4
- Weak or faulty spark plug or ignition coil on cylinder #4
- Low compression in cylinder #4 due to worn rings or valves
02. Symptoms You Will Notice
- Rough idle or engine vibration
- Check Engine Light illuminated
- Decreased fuel economy
- Possible misfire or hesitation during acceleration
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data to confirm cylinder #4 is the issue.
Step 2: Perform a visual inspection of vacuum hoses and intake manifold gaskets near cylinder #4 for leaks.
Step 3: Swap spark plug and ignition coil from cylinder #4 to another cylinder; if the misfire moves, replace the faulty component.
Step 4: Test fuel injector on cylinder #4 for proper spray pattern and resistance; clean or replace if necessary.
Step 5: Perform a compression test on cylinder #4; if low, inspect for mechanical issues like worn rings or valves.
04. Commonly Affected Makes
05. 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 spark plug replacement is around $50-$100, while a fuel injector or ignition coil can cost $100-$150. Diagnostic fees are typically $50-$100.