Common Symptoms
- Check Engine Light illuminated
- Rough idle or engine hesitation
- Reduced engine performance or power loss
- Increased NOx emissions
- Poor fuel economy
- Engine may enter limp mode
Most Likely Root Causes
- Faulty EGR position sensor B
- Damaged or corroded wiring harness to EGR sensor B
- Short to voltage in EGR sensor B circuit
- Failed EGR valve assembly
- Corroded or loose electrical connector at EGR sensor B
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Component Location
EGR position sensor B is typically mounted on or integrated into the EGR valve assembly near the intake manifold.
Manufacturer Notes
Some manufacturers integrate dual EGR position sensors into the valve assembly requiring complete unit replacement if sensor B fails.
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