POWERSTROKE-P0671 moderate Power Stroke ›

Cylinder 1 Glow Plug Circuit

The POWERSTROKE-P0671 (Power Stroke) diesel fault code means: Cylinder 1 Glow Plug Circuit. 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-P0671?

  • Check Engine Light on
  • Hard starting when cold
  • White smoke or rough running after a cold start

What Causes POWERSTROKE-P0671? (Most Likely First)

  • Failed cylinder 1 glow plug High
  • Damaged wire or loose connection at the glow plug High
  • Glow plug control module fault Low

Can I Still Drive with POWERSTROKE-P0671?

Yes, but fix soon. POWERSTROKE-P0671 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 P0671 mean on a Power Stroke?

P0671 means Cylinder 1 Glow Plug Circuit. The glow plug control system has detected a fault in the circuit for the cylinder 1 glow plug.

Is P0671 a Power Stroke-specific code?

No. P0671 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-P0671?

  1. Measure the cylinder 1 glow plug resistance and compare it with the other cylinders and the specification.

  2. Inspect the glow plug wire and terminal.

  3. Check the control module output to cylinder 1 if the plug and wiring test good.

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0671 as a generic OBD-II code)

P0671 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 P0671 Duramax moderate Cylinder 1 Glow Plug Circuit

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

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