POWERSTROKE-P1668 moderate Power Stroke ›

PCM - IDM Communication Fault

The POWERSTROKE-P1668 (Power Stroke) diesel fault code means: PCM - IDM Communication Fault. This is a moderate severity code.

My Garage →
Keep driving?
No — stop driving
DIY difficulty
advanced
Estimated cost
$300-$1,200
Mobile mechanic network · I-5 corridor pilot

Down with a Power Stroke fault on the road?

We are building a network of verified mobile diesel and reefer technicians along the freight corridor. It is not live yet — no one can be dispatched to you today. You can see where the pilot is launching and register interest.

View pilot availability →

What Are the Symptoms of POWERSTROKE-P1668?

  • CEL
  • Stalling

What Causes POWERSTROKE-P1668? (Most Likely First)

  • Damaged communication wire PCM-IDM Likely
  • Failed IDM Likely

Can I Still Drive with POWERSTROKE-P1668?

No — stop driving. POWERSTROKE-P1668 is rated moderate severity. Continuing to drive in this state risks further damage — get it looked at before your next trip.

Frequently Asked Questions

What is P1668 on a 7.3L Power Stroke?

P1668 on a 7.3L Power Stroke (1994-2003) indicates: PCM - IDM Communication Fault. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.

Can I drive with P1668 on my Power Stroke?

No. Stop driving and arrange for towing. Continued operation risks serious engine or emissions system damage.

How much does it cost to fix P1668?

Repair cost is typically $300-$1,200 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-P1668?

  1. Check continuity on the IDM comm wires.

  2. Replace IDM.

P1668 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 P1668

Which Vehicles Commonly Get POWERSTROKE-P1668?

  • 1994.5-1997 Ford F-250/F-350 7.3L Power Stroke
  • 1999-2003 Ford F-250/F-350 Super Duty 7.3L Power Stroke
  • 1999-2003 Ford F-450/F-550 Super Duty 7.3L Power Stroke
  • 1994.5-2003 Ford E-350/E-450 7.3L Power Stroke
  • 2000-2003 Ford Excursion 7.3L Power Stroke

Explore More

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

Was this helpful?

Send this to whoever is fixing the truck — your tech, or the person asking what the fault means.