DURAMAX-P0671 moderate Duramax ›

Cylinder 1 Glow Plug Circuit

The DURAMAX-P0671 (Duramax) 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
intermediate
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What Are the Symptoms of DURAMAX-P0671?

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

What Causes DURAMAX-P0671? (Most Likely First)

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

Can I Still Drive with DURAMAX-P0671?

Yes, but fix soon. DURAMAX-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.

Common Fixes by Vehicle

What techs usually find when diagnosing DURAMAX-P0671 on specific platforms — tap a platform for the fix and the exact part:

2006-2016 GMC/Chevy 2500/3500 6.6L Duramax (LBZ/LMM/LML) Moderate DIY

P0671 (glow plug cylinder 1 circuit) on the Duramax is usually a failed glow plug, not the harness. Glow plugs on the Duramax last 80-120K miles. Replace in sets of 8 to avoid repeat visits; OEM plug is $30 each. Access on the driver side is tight -- many techs remove the fender liner. Use anti-seize on threads. Critical: the 6.6L uses short-tip glow plugs; wrong-length plugs can contact the piston.

Labor: 3-6 hours
Common fix part Duramax Glow Plug Set (8x) View on Amazon→ Compare fitment at PartsGeek→

Frequently Asked Questions

What does P0671 mean on a Duramax?

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 Duramax-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 GM uses to set it on its diesels are in GM service information.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose DURAMAX-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 controller 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 Power Stroke moderate Cylinder 1 Glow Plug Circuit

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