Injector Circuit High - Cylinder 10
The P0291 code means the vehicle's onboard diagnostic system has detected: Injector Circuit High - Cylinder 10. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $150 - $700 (parts and labor)
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Common Symptoms
- Check Engine Light on
- No fuel to cylinder 10
- Misfire
- Reduced power
Probable Causes (Ranked by Likelihood)
- Open circuit in cylinder 10 injector wiring Very High
- Failed injector (open coil) High
- Disconnected connector Moderate
- PCM driver open Low
Step-by-Step Diagnostic Procedure
-
Measure injector resistance.
-
Check connector.
-
Test wiring continuity.
-
Replace injector if needed.
Frequently Asked Questions
What happens with cylinder 10 not firing?
The engine runs on 9 cylinders with noticeable vibration and power loss. The Bank 2 catalytic converter is at risk.
Is cylinder 10 hard to access?
On Ford V10 truck engines, it is at the very rear and may require intake manifold removal. On mid-engine sports cars, rear engine cover removal is needed.
Can low fuel pressure mimic P0291?
No, low fuel pressure would affect all cylinders. P0291 is specific to cylinder 10 electrical circuit.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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