EGR Stuck Open
The YANMAR-P042E (Yanmar) diesel fault code means: EGR Stuck Open. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $50-$700
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Common Symptoms
- Rough idle, white smoke
Probable Causes (Ranked by Likelihood)
- Carbon holding EGR pintle open Very Likely
- Failed EGR return spring Possible
Step-by-Step Diagnostic Procedure
Remove EGR valve for inspection.
Clean pintle and seat.
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.
P042E on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: