POWERSTROKE-P2266 moderate Power Stroke ›

Water in Fuel Sensor Circuit Low

The POWERSTROKE-P2266 (Power Stroke) diesel fault code means: Water in Fuel Sensor Circuit Low. This is a moderate severity code.

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Keep driving?
Yes, but fix soon
DIY difficulty
beginner
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What Are the Symptoms of POWERSTROKE-P2266?

  • Check Engine Light on
  • Water-in-fuel warning that may be true or false

What Causes POWERSTROKE-P2266? (Most Likely First)

  • Water actually present in the fuel filter housing High
  • Failed water-in-fuel sensor High
  • Signal wire shorted to ground Moderate

Can I Still Drive with POWERSTROKE-P2266?

Yes, but fix soon. POWERSTROKE-P2266 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.

Frequently Asked Questions

What does P2266 mean on a Power Stroke?

P2266 means Water in Fuel Sensor Circuit Low. The water-in-fuel sensor signal is below its normal range.

Is P2266 a Power Stroke-specific code?

No. P2266 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions Ford uses to set it on its diesels are in Ford service information.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose POWERSTROKE-P2266?

  1. Drain the fuel filter housing or water separator and check for water first.

  2. Inspect the sensor and its connector.

  3. Check the sensor circuit against the service specification.

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P2266 as a generic OBD-II code)

P2266 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 P2266

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

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