Exhaust Valve Control Solenoid A Circuit
The POWERSTROKE-P0078 (Power Stroke) diesel fault code means: Exhaust Valve Control Solenoid A Circuit. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- intermediate
- Estimated cost
- $150-$500
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Common Symptoms
- CEL
- Low boost
Probable Causes (Ranked by Likelihood)
- Failed exhaust back pressure valve solenoid Likely
- Wiring fault Likely
Step-by-Step Diagnostic Procedure
Test solenoid resistance.
Replace solenoid.
Frequently Asked Questions
What is P0078 on a 6.0L Power Stroke?
P0078 on a 6.0L Power Stroke (2003-2007) indicates: Exhaust Valve Control Solenoid A Circuit. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.
Can I drive with P0078 on my Power Stroke?
Only drive short distances to get to a repair facility. Continued operation may cause further damage.
How much does it cost to fix P0078?
Repair cost is typically $150-$500 depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.
P0078 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: