YANMAR-P042E serious Yanmar ›

EGR Stuck Open

The YANMAR-P042E (Yanmar) diesel fault code means: EGR Stuck Open. This is a serious severity code.

Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.

My Garage →
Keep driving?
Limited driving only
DIY difficulty
intermediate
Estimated cost
$50-$700

What Are the Symptoms of YANMAR-P042E?

  • Rough idle, white smoke

What Causes YANMAR-P042E? (Most Likely First)

  • Carbon holding EGR pintle open Very Likely
  • Failed EGR return spring Possible

Can I Still Drive with YANMAR-P042E?

Limited driving only. YANMAR-P042E is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is Yanmar code P042E?

Yanmar P042E: EGR Stuck Open.

Can I keep operating with Yanmar code P042E?

Limited operation only -- finish task then shut down.

How much does Yanmar P042E cost to fix?

Typical cost: $50-$700. Yanmar SmartAssist / YDT diagnostic software is often required.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose YANMAR-P042E?

  1. Remove EGR valve for inspection.

  2. Clean pintle and seat.

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 — definition not reliably documented Isuzu serious EGR Valve Stuck Open — definition not reliably documented Kubota serious EGR Valve Stuck Open MaxxForce serious EGR Valve Stuck Open — definition not reliably documented Perkins serious EGR Valve Stuck Open Power Stroke serious EGR 'A' Control Stuck Open

Which Vehicles Commonly Get YANMAR-P042E?

  • Yanmar SA221 / SA324 / SA424 compact tractors
  • Yanmar YT235 / YT347 / YT359 compact tractors
  • Yanmar LX4100 / LX4900 utility tractors
  • Yanmar ViO17 / ViO25 / ViO35 / ViO45 / ViO55 / ViO80 mini excavators
  • Yanmar B27-3 / B37-3 / B50-3 compact excavators

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

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