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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What Are the Symptoms of MAXXFORCE-P042E?
- Rough idle
- White smoke
- CEL
What Causes MAXXFORCE-P042E? (Most Likely First)
- Carboned EGR valve stuck open Very Likely
Can I Still Drive with MAXXFORCE-P042E?
Short distances only. MAXXFORCE-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 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.
What actually makes the computer set this EGR code?
California's heavy-duty OBD regulation sets the low-flow trip point where a decrease from the manufacturer's specified EGR rate would push NMHC, CO or NOx past 2.0 times the applicable standards, or PM past the standard plus 0.02 g/bhp-hr (Title 13 CCR 1971.1, section (e)(3.2.1)). Note the second route: it must also flag the case where the EGR system has hit its control limits and simply cannot reach the commanded flow — so this code can set with the valve working and the system still unable to deliver. This threshold comes from the heavy-duty OBD regulation, which covers 2010 and later heavy-duty engines. If your engine is in a pickup at or under 14,000 lb GVWR it is certified under the separate medium-duty rule instead, so treat this as the design intent rather than your engine's exact limit.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose MAXXFORCE-P042E?
Remove valve and clean with solvent.
Replace if sticking persists.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- California Code of Regulations, Title 13 section 1971.1 (Heavy-Duty OBD)malfunction criteria, section (e)
- 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:
Which Vehicles Commonly Get MAXXFORCE-P042E?
- International TerraStar MaxxForce 7
- International 4300 DuraStar MaxxForce 7
- International WorkStar 7300 MaxxForce 7
- IC Bus CE-Series MaxxForce 7
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