POWERSTROKE-P0308 serious Power Stroke ›

Cylinder 8 Misfire Detected

The POWERSTROKE-P0308 (Power Stroke) diesel fault code means: Cylinder 8 Misfire Detected. This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
advanced
Estimated cost
$500-$9,000 (piston/liner damage is the worst case)
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What Are the Symptoms of POWERSTROKE-P0308?

  • Cylinder 8 misfire
  • Rough running
  • CEL flashing possible
  • Vibration at idle

What Causes POWERSTROKE-P0308? (Most Likely First)

  • Cracked piston (6.4L has piston-cracking issues on deleted / over-fueled trucks) Very Likely
  • Failed injector (6.4L piezo injectors are expensive) Likely
  • Low compression from broken ring or melted piston Possible
  • Stuck open injector flooding the cylinder Possible

Can I Still Drive with POWERSTROKE-P0308?

Short distances only. POWERSTROKE-P0308 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is P0308 on a 6.4L Power Stroke?

P0308 on a 6.4L Power Stroke (2008-2010) indicates: Cylinder 8 Misfire Detected. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.

Can I drive with P0308 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 P0308?

Repair cost is typically $500-$9,000 (piston/liner damage is the worst case) depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose POWERSTROKE-P0308?

  1. Perform relative compression test via scan tool.

  2. If compression is low on one cylinder, borescope through injector hole or glow plug port.

  3. Check injector balance rates / CCT data.

  4. Replace injectors as a set on 6.4L if multiple cylinders show fueling issues.

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0308 as a generic OBD-II code)

P0308 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Gas / Automotive (OBD-II) Generic OBD-II definition for P0308 Duramax serious Cylinder 8 Misfire Detected

Which Vehicles Commonly Get POWERSTROKE-P0308?

  • 2008-2010 Ford F-250 Super Duty 6.4L Power Stroke
  • 2008-2010 Ford F-350 Super Duty 6.4L Power Stroke
  • 2008-2010 Ford F-450/F-550 Super Duty 6.4L Power Stroke

Explore More

More Power Stroke codes → Diesel home All diesel codes Heavy-duty Guides

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