PERKINS-P042E serious Perkins ›

EGR Valve Stuck Open

The PERKINS-P042E (Perkins) diesel fault code means: EGR Valve Stuck Open. This is a serious severity code.

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Keep driving?
Yes, with caution
DIY difficulty
intermediate
Estimated cost
$60-$160 cleaning
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Common Symptoms

  • Rough idle
  • White smoke

Probable Causes (Ranked by Likelihood)

  • Carbon on seat (common on 1104D industrial light-idle) Very Likely

Frequently Asked Questions

What is Perkins fault code P042E?

Perkins P042E means: EGR Valve Stuck Open. Serious code -- address promptly to avoid inducement / further damage.

Can I keep operating with Perkins P042E?

Serious fault -- you can move the machine to a shop but don't run it under load. Diagnose with Perkins EST / CAT ET (kin to CAT-badged machines).

How much does it cost to fix Perkins P042E?

Repair cost range: $60-$160 cleaning.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Remove and clean EGR valve.

Sources 1

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

  • SAE J2012Diagnostic Trouble Code Definitions (defines P042E as a generic OBD-II code)

P042E on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Hino serious EGR Valve Stuck Open Isuzu serious EGR Valve Stuck Open Kubota serious EGR Valve Stuck Open MaxxForce serious EGR Valve Stuck Open Power Stroke serious EGR 'A' Control Stuck Open Yanmar serious EGR Stuck Open

Commonly Affected Vehicles

  • CAT and JCB compact wheel loaders with Perkins 854E
  • CAT 244D / 246D / 262D skid steers (Perkins-derived)
  • JCB 3CX / 4CX backhoes with 1104D / 1204E
  • Manitou telehandlers with Perkins 1104D / 1204E
  • Perkins 2506 / 2806 industrial gensets

Explore More

More Perkins codes → Diesel home All diesel codes Heavy-duty Guides

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