OBD-II code · Powertrain (generic)
P049B EGR B Flow Insufficient Detected
Same as P049A but specifically with measured flow below the required rate - typically EGR valve sticking closed or cooler heavily clogged.
Is it safe to drive with P049B?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyEGR valve B sticking closed
- PossibleEGR cooler B heavily clogged with soot
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1.5–5 h
- Emissions test
- Likely to fail
- Parts involved
- Egr Valve B, Egr Cooler B
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.