POWERSTROKE-P204F moderate Power Stroke ›

Reductant System Performance

The POWERSTROKE-P204F (Power Stroke) diesel fault code means: Reductant System Performance. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
advanced
Estimated cost
$300-$2,500
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What Are the Symptoms of POWERSTROKE-P204F?

  • CEL
  • DEF warning
  • Limited MPH / derate (100 then 55 then 5 mph)

What Causes POWERSTROKE-P204F? (Most Likely First)

  • DEF injector clogged with crystal Very Likely
  • Failed DEF pump Likely
  • NOx sensor failure sending bad data Likely
  • SCR catalyst aging Possible

Can I Still Drive with POWERSTROKE-P204F?

Short distances only. POWERSTROKE-P204F is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is P204F on a 6.7L Power Stroke (Scorpion)?

P204F on a 6.7L Power Stroke (Scorpion) (2011-present) indicates: Reductant System Performance. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.

Can I drive with P204F 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 P204F?

Repair cost is typically $300-$2,500 depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose POWERSTROKE-P204F?

  1. Monitor DEF pump pressure and DEF injector command on scan tool.

  2. Remove DEF injector and inspect for crystallized urea blockage.

  3. Test both NOx sensors -- often one reads out of range.

  4. Replace individual components, not entire assembly, when possible.

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P204F as a generic OBD-II code)

P204F 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 P204F Duramax serious Reductant System Performance Bank 1 Hino serious Reductant System Performance Isuzu serious Reductant System Performance Kubota serious Reductant Quality Sensor Performance MaxxForce moderate Reductant System Performance PACCAR serious Reductant System Performance

Which Vehicles Commonly Get POWERSTROKE-P204F?

  • 2011-present Ford F-250 Super Duty 6.7L Power Stroke
  • 2011-present Ford F-350 Super Duty 6.7L Power Stroke
  • 2011-present Ford F-450/F-550 Super Duty 6.7L Power Stroke
  • 2015-2019 Ford F-650/F-750 6.7L Power Stroke

Explore More

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

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