Cylinder 5 Contribution/Balance Fault
The P0275 code indicates that the Engine Control Module (ECM) has detected a misfire or imbalance in cylinder 5's power contribution relative to the other cylinders. This is typically caused by a faulty fuel injector, ignition issue, or mechanical problem within cylinder 5. The ECM monitors crankshaft speed variations to identify cylinders that are not contributing equally, and when cylinder 5 shows a significant deviation, this code is set.
01. Most Common Causes
- Faulty fuel injector on cylinder 5
- Ignition coil or spark plug failure on cylinder 5
- Low compression in cylinder 5
- Wiring or connector issues to injector or coil
02. Symptoms You Will Notice
- Engine misfire or rough idle
- Check Engine Light illuminated
- Reduced engine power and fuel economy
- Possible hesitation or stumbling during acceleration
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Perform a cylinder contribution test using a scan tool to confirm cylinder 5 is weak.
Step 3: Inspect spark plug and ignition coil on cylinder 5; swap with another cylinder to see if misfire follows.
Step 4: Test fuel injector on cylinder 5 for proper operation (resistance, flow, and electrical signal).
Step 5: Perform a compression test on cylinder 5 to rule out mechanical issues.
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 misfire can damage the catalytic converter and cause further engine damage. Limp home if necessary.
How much does it cost to fix?▼
Costs vary: replacing a spark plug or coil is $50-$150; a fuel injector replacement is $150-$400; internal engine repairs can exceed $1000.