Cylinder 4 Balance Fault
Indicates a power imbalance in cylinder number 4.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine is not firing properly in cylinder 4, which can cause rough running or misfires.
What the computer is actually seeing
The Engine Control Module (ECM) detects a difference in power output from cylinder 4 compared to the other cylinders during operation.
What a healthy reading looks like
Expected torque/voltage between cylinders should be within 5-10% of each other.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check for any other related DTCs and record them; if present, address those issues first.
- 22. Perform a visual inspection of wiring and connectors for cylinder 4. Look for signs of damage, corrosion, or loose connections; repair as necessary.
- 33. Check the spark plug in cylinder 4 for wear and gaps. Replace if worn.
- 44. Test the fuel injector for cylinder 4 using a noid light or multimeter; it should pulse on the test. Replace if not functioning properly.
- 55. Conduct a compression test on cylinder 4; values should be within 10% of other cylinders. If low, investigate possible mechanical issues like valve failure or head gasket problems.
- 66. Scan for any air intake leaks in the manifold or vacuum lines. Inspect for cracks or loose fittings; repair any leaks found.
Common causes
- Faulty fuel injector for cylinder 4
- Compression loss in cylinder 4
- Vacuum leaks around intake manifold for cylinder 4
- Wiring or connector issues to the injector or sensor for cylinder 4
- Faulty spark plug or ignition coil for cylinder 4
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix it soon as it can lead to further engine damage if ignored.
Will this issue come back after clearing the code?
If the underlying issue isn't resolved, the code will likely reappear.
Why does this code relate to cylinder 4 only?
The computer monitors each cylinder's performance; a fault noted specifically in cylinder 4 indicates a localized issue.
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