EGR Valve Stuck Open
The MAXXFORCE-P042E (MaxxForce) diesel fault code means: EGR Valve Stuck Open. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- intermediate
- Estimated cost
- $350-$1,800
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Common Symptoms
- Rough idle
- White smoke
- CEL
Probable Causes (Ranked by Likelihood)
- Carboned EGR valve stuck open Very Likely
Step-by-Step Diagnostic Procedure
Remove valve and clean with solvent.
Replace if sticking persists.
Frequently Asked Questions
What is P042E on a MaxxForce 7 (6.4L)?
P042E on a MaxxForce 7 (6.4L) (2007-2013) indicates: EGR Valve Stuck Open. This is a known fault code on the MaxxForce engine family and typically points to the causes listed above.
Can I drive with P042E on my MaxxForce?
Only drive short distances to reach a repair facility. Continued operation may cause further damage or progressive derate.
How much does it cost to fix MaxxForce P042E?
Repair cost is typically $350-$1,800 depending on the underlying cause and shop rate. Many MaxxForce faults (especially EGR cooler, head bolt, and VGT repairs) are major expenses that drove fleet owners to repower with Cummins or retire these trucks early.
P042E on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: