P042EEGR A Control Stuck Open
EGR valve A is mechanically stuck open — exhaust gas continues to flow into the intake at all times, causing rough idle and lean condition during acceleration.
Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Sistema de Escape · Catalizador y sensores O₂
La falla se localiza en la línea de escape: catalizador, sondas lambda (O₂) o sistema EGR.
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Symptoms You Will Notice
What you may observe when this code appears
- Check engine light on Pinging or knocking under load Power loss and hesitation Possible rough idle Failed emissions inspection (NOx)
Possible Causes
The components or conditions that trigger this code
- 1Carbon buildup holds valve open Carbon or debris buildup preventing free movement Component wear with age - mechanical play
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: medium. Estimated time: 0.7-3 hours. Estimated cost: €80-€
- 2DIY possible
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Varies by diagnosis
* Diagnosis only: $50–$150
Quick Info
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