OBD-II code · Powertrain (generic, extended)

P23E8 EGR C Flow Excessive Detected

Same as P049C 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 P23E8?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyEGR valve C sticking open

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

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.