P049C
EGR B Flow Excessive Detected
EGR (emissions)
Generic OBD-II
Medium
What it means
P049C means the engine computer sees more exhaust gas recirculation through the second (B) EGR valve than commanded. Too much recirculated exhaust dilutes the air-fuel mix, so the valve is usually stuck open or carboned up, causing rough idle, hesitation, and sometimes stalling. The car generally still drives, but running quality suffers until it's fixed.
Medium
Can I keep driving? Usually yes, but excessive EGR can cause rough idle, hesitation, or stalling; have it checked soon to avoid drivability problems.
Common symptoms
What you'll notice
- Check-engine light on
- Rough or unstable idle
- Hesitation or stumble under light throttle
- Occasional stalling, especially at idle or low speed
Common causes
Most likely first
- EGR B valve stuck or held open by carbon buildupLikely
- Faulty EGR valve or actuator not closing fullyCommon
- EGR position/feedback sensor reading incorrectlyCommon
- Faulty EGR control solenoid commanding too much flowLess often
- Carbon-fouled EGR passages disturbing meteringLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and note the conditions where excessive flow is reported (often idle).
- Inspect the EGR B valve and passages for carbon holding the valve open; clean as needed.
- Check the EGR position/feedback sensor reading against actual valve position.
- Test the control solenoid and actuator; replace the EGR valve if it won't seat closed.
- Clear the code and confirm idle quality and flow return to normal.
FAQ
Quick answers
Is it safe to drive with P049C?+
Short trips are usually fine, but too much recirculated exhaust can cause stalling and rough running. Have it cleaned or repaired soon.
Can I just clear P049C?+
It clears, but returns if the EGR valve is still stuck open or the passages are carboned up. Clean or repair the valve first.
Related codes
Often seen with P049C
Read & clear P049C yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX