OBD-II code · Powertrain (generic, extended)

P24C4 EGR Cooler Bypass Position Sensor Exceeded Learning Limit Bank 1

The bypass valve position sensor learning has reached its software-side limit on bank 1 - typically heavy soot deposits have shifted the mechanical zero beyond the design adaptation range.

Is it safe to drive with P24C4?

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

Common causes

  • Most likelyHeavy carbon build-up on valve seat

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
1–4 h
Emissions test
Likely to fail
Parts involved
Egr Cooler Bypass Position Sensor B1

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