OBD
P049B
EGR B Flow Insufficient Detected
What it means
P049B means EGR B Flow Insufficient Detected.
Check these first
- A dirty EGR valve limiting flow
- A failed EGR flow sensor reading low
- A blocked EGR tube
- A vacuum leak past the EGR valve
What to do next
- Command the EGR B valve open and watch flow on a scan tool
- Clean the EGR valve and EGR passages
- Check the EGR flow sensor output
- Inspect the EGR tube for a blockage
- Clear the code and retest
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Updated
Generic SAE J2012 definition. Last updated 2026-10-10.