Cylinder 6 Misfire Detected
The DURAMAX-P0306 (Duramax) diesel fault code means: Cylinder 6 Misfire Detected. This is a serious severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0306?
- Check Engine Light on, possibly flashing
- Rough running
- Loss of power
- Possible smoke from the exhaust
What Causes DURAMAX-P0306? (Most Likely First)
- Cylinder 6 injector fault High
- Injector wiring or connector fault Moderate
- Low compression on cylinder 6 Moderate
- Fuel supply or quality problem Low
Can I Still Drive with DURAMAX-P0306?
Yes, with caution. DURAMAX-P0306 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0306 mean on a Duramax?
P0306 means Cylinder 6 Misfire Detected. The engine computer has detected that cylinder 6 is misfiring.
Is P0306 a Duramax-specific code?
No. P0306 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions GM uses to set it on its diesels are in GM service information.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose DURAMAX-P0306?
Check injector balance or contribution data on a scan tool.
Inspect the cylinder 6 injector wiring and connector.
Run a compression test before replacing the injector.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0306 as a generic OBD-II code)
P0306 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
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