What it means
The control module has reached the maximum fuel-trim correction for cylinder 6. This indicates a cylinder-specific mixture correction limit; the code alone does not identify the underlying cause.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The engine computer adjusts fuel for cylinder 6 to keep combustion balanced. This code sets when cylinder 6's fuel-trim correction reaches its upper calibrated limit, which can result from restricted fuel, an air leak affecting that cylinder, or a misleading input; the code alone does not identify the cause.
Common causes
Most likely first.
- Injector restricted or clogged on cylinder 6
- Air leak affecting cylinder 6
- Low fuel pressure or delivery problem
- Cylinder 6 sensor, wiring, or control fault
Symptoms
- Check-engine light
- Rough idle or engine vibration
- Misfire or hesitation
- Reduced engine power
How to diagnose it
- Review freeze-frame data, cylinder-specific trim information, and misfire counts to identify when cylinder 6 reaches its upper limit.
- Inspect the intake passages, vacuum connections, and seals serving cylinder 6 for leaks.
- Check cylinder 6 injector connector and wiring for damage, corrosion, or poor contact.
- Compare cylinder 6 injector flow and contribution with the other cylinders using suitable scan-tool or balance tests.
- Check fuel pressure, relevant sensor inputs, and cylinder 6 control circuits against the manufacturer's specification.
Common fixes
- Repair an air leak affecting cylinder 6.
- Clean or replace a restricted cylinder 6 injector based on test results.
- Repair damaged cylinder 6 injector wiring or connections.
- Correct a fuel delivery or sensor/control fault identified by testing.
Can I keep driving?
Gentle, short driving may be possible if the engine runs smoothly, but avoid hard acceleration and heavy loads. Stop when safe if it misfires or loses power, since a continuing misfire can damage the catalytic converter.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.