Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine hesitation
- Poor fuel economy
- Engine ping or spark knock under load
- Reduced engine power or performance
- Failed emissions test
Most Likely Root Causes
- EGR valve stuck open or failing to close properly
- Carbon buildup preventing EGR valve from seating
- Faulty EGR vacuum solenoid or control valve
- Damaged or leaking EGR vacuum lines
- Failed EGR position sensor providing incorrect feedback
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Component Location
The EGR valve is typically mounted on the intake manifold or cylinder head with a passage connecting to the exhaust manifold.
Manufacturer Notes
Some manufacturers use vacuum-operated EGR systems while others use electronic actuators, affecting diagnostic approach and component replacement procedures.
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