Cylinder 12 Fuel Trim at Min Limit
The P02C7 code indicates that the fuel trim for cylinder 12 has reached its minimum limit, meaning the engine control module (ECM) is detecting an excessively rich air-fuel mixture in that cylinder and has reduced fuel delivery as much as possible. This can be caused by a stuck-open fuel injector, high fuel pressure, a faulty oxygen sensor, or a vacuum leak. If left unaddressed, it can lead to poor fuel economy, engine misfires, and catalytic converter damage.
01. Most Common Causes
- Stuck-open fuel injector on cylinder 12
- High fuel pressure (faulty fuel pressure regulator)
- Faulty oxygen sensor (pre-cat or post-cat)
- Vacuum leak causing unmetered air
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Rough idle or engine misfire
- Poor fuel economy
- Strong fuel smell from exhaust
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data.
Step 2: Inspect fuel injector on cylinder 12 for leakage or sticking.
Step 3: Check fuel pressure and regulator operation.
Step 4: Test oxygen sensor readings and response.
Step 5: Inspect for vacuum leaks using smoke test.
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 it can cause catalytic converter damage and poor engine performance.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on the root cause (e.g., injector replacement vs. sensor replacement).