CMP Sensor Circuit Malfunction
The POWERSTROKE-P0340-67 (Power Stroke) diesel fault code means: CMP Sensor Circuit Malfunction. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- beginner
- Estimated cost
- $100-$300
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Common Symptoms
- Long crank
- Stall at idle
- CEL
Probable Causes (Ranked by Likelihood)
- Failed CMP sensor Very Likely
- Harness fault Likely
Step-by-Step Diagnostic Procedure
Scope CMP signal.
Replace sensor.
Frequently Asked Questions
What is P0340 on a 6.7L Power Stroke (Scorpion)?
P0340 on a 6.7L Power Stroke (Scorpion) (2011-present) indicates: CMP Sensor Circuit Malfunction. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.
Can I drive with P0340 on my Power Stroke?
Yes, you can generally drive with this code, but diagnose it soon to prevent further damage.
How much does it cost to fix P0340?
Repair cost is typically $100-$300 depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.