What this code means

The PCM detected that the EGR valve is not fully closing when commanded closed. The EGR valve position sensor voltage remains above 0.29V when the valve should be closed. This code is most commonly caused by carbon buildup on the EGR valve pintle that prevents full closure. Over time, the original learned closed-position signal drifts as the position sensor wears.

Symptoms

• Check Engine Light
• Rough or erratic idle
• Engine knocking or pinging on acceleration
• Black smoke from tailpipe
• Reduced fuel economy
• Hard starting
• Engine stalling

Common causes

• Carbon buildup on EGR valve pintle (most common)
• Worn EGR valve position sensor
• EGR valve mechanically stuck open
• Damaged EGR valve wiring
• Excessive wear of EGR valve internals
• PCM failure (rare)

Diagnostic steps

1. Monitor EGR valve position voltage with scan tool when commanded closed (should be below 0.29V)
2. Remove and inspect EGR valve for carbon deposits
3. Clean EGR valve pintle and seat
4. Test EGR position sensor through range of motion
5. Check wiring and connector

Repair notes

Remove and clean EGR valve of carbon deposits. If cleaning does not resolve, replace EGR valve assembly. The EGR position sensor is often integrated into the valve.

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