Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine stumbling
- Poor fuel economy
- Increased emissions during testing
- Engine hesitation during acceleration
- Slight loss of power under load
Most Likely Root Causes
- Faulty EGR valve or stuck EGR valve
- Damaged or corroded wiring harness to EGR valve
- Failed EGR valve solenoid or control circuit
- Poor electrical connection at EGR valve connector
- Failed powertrain control module (PCM)
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Component Location
The EGR valve is typically mounted on the intake manifold or cylinder head, connected to the exhaust manifold via a metal tube.
Manufacturer Notes
Some manufacturers use vacuum-operated EGR systems while others use electronic solenoid-controlled valves with different diagnostic approaches.
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