Ignition Coil C Primary Control Circuit Low
The P2304 code means the vehicle's onboard diagnostic system has detected: Ignition Coil C Primary Control Circuit Low. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $50 - $300 (parts and labor)
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Common Symptoms
- Engine misfire on cylinder 3
- Check Engine Light flashing or steady
- Rough idle with noticeable vibration
- Reduced acceleration performance
- Unburned fuel smell from tailpipe
Probable Causes (Ranked by Likelihood)
- Failed ignition coil C Very High
- Damaged wiring to coil C High
- Corroded coil C electrical connector Moderate
- Worn spark plug causing coil overload Moderate
Step-by-Step Diagnostic Procedure
-
Swap coil C with another cylinder coil to confirm diagnosis
-
Inspect spark plug on cylinder 3 for wear or fouling
-
Check coil C connector for oil or water contamination
-
Measure coil C primary winding resistance
-
Inspect the coil boot for carbon tracking or cracks
Frequently Asked Questions
Can I drive with code P2304?
Short distances only. A misfiring engine should be repaired promptly to avoid catalytic converter damage.
What causes P2304?
Most commonly a failed ignition coil on cylinder 3. Worn spark plugs can also cause premature coil failure by making the coil work harder.
Is P2304 expensive to fix?
Typically $50 to $300. Coil and spark plug replacement is a common DIY repair. Always replace both together for best results.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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