P042E

EGR A Control Stuck Open

Moderate severity

EGR A Control Stuck Open: the control module has detected this fault condition. Without valid EGR feedback the ECU disables exhaust gas recirculation and may set further EGR codes.

Common causes

Carbon buildup holds valve open
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $90-880
Carbon or debris buildup preventing free movement
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $90-880
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P042E mean?

P042E means "EGR A Control Stuck Open". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P042E?

carbon buildup holds valve open; carbon or debris buildup preventing free movement; component wear with age - mechanical play — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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