P23E6EGR C Control Stuck Closed
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- With P23E6 the module concludes that EGR valve C does not open when commanded and stays at or near its closed stop. The consequence is the reverse of P23E5: the engine runs smoothly, but the exhaust share from this path is missing, combustion temperature and NOx go up, and a petrol engine may knock more readily. Typical reasons are a valve glued shut by soot, a seized shaft, a stripped drive gear or a motor that no longer delivers enough torque against the deposits. The counterparts for valves A and B are P042F and P045F; GM's 2018 diesel tables group P042F with P042E as position deviation faults. No manufacturer documents P23E6 publicly; CARB requires EGR systems to be monitored for insufficient flow and faulty control. Low flow from this path is P23E7.
- What you may notice
- No change in driving, but higher NOx
- Possible knocking on petrol engines
- Warning lamp
- Likely causes
- LikelyValve C glued shut by soot
- PossibleSeized shaft or stripped drive gear
- RareActuator motor too weak to break the valve free
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €100 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.