OBD-II code · Powertrain (generic, extended)
P23E7 EGR C Flow Insufficient Detected
Same as P049B on EGR loop C. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.
Is it safe to drive with P23E7?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyEGR cooler C 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 C, Egr Cooler C
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.