P0272: Cylinder 4 Contribution/Balance
Do not keep driving
Expect noticeably rough running. Ask for a compression or leak-down test if the injector tests good.
What this code means
Cylinder 4 is contributing measurably less than its neighbours. On four-cylinder engines a single weak cylinder is 25% of the engine's output, so the roughness is pronounced and the vibration obvious.
Likely causes
Start here
- Clogged fuel injectors · moderate
- Low engine compression · specialist
- Burnt or leaking valve · specialist
- Failed fuel injector · moderate
Less common
- Worn piston rings · specialist
- Head gasket failure · specialist
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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What makes one worth reading:
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