EGR Valve Stuck Open
The PERKINS-P042E (Perkins) diesel fault code means: EGR Valve Stuck Open. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- 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
Step-by-Step Diagnostic Procedure
Remove and clean EGR valve.
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.
P042E on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: