Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine stumbling
- Engine hesitation during acceleration
- Increased NOx emissions
- Failed emissions test
- Slight decrease in fuel economy
Most Likely Root Causes
- Carbon buildup blocking EGR valve or passages
- Faulty EGR valve stuck open or closed
- Clogged or restricted EGR passages in intake manifold
- Vacuum leak in EGR vacuum lines or hoses
- Failed DPFE or EGR pressure sensor
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Component Location
EGR valve is typically mounted on the intake manifold or cylinder head with passages connecting exhaust and intake systems.
Manufacturer Notes
Ford vehicles with DPFE sensors are particularly prone to sensor failure causing false EGR flow codes.
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