OBD-II code · Powertrain (generic, extended)
P24D4 EGR Cooler Coolant Pump Feedback Circuit
A general circuit fault on the feedback line that the EGR cooler coolant pump reports speed on. 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 P24D4?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen in feedback wiring
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
- Often, with basic tools
- Typical labour
- 1–3 h
- Emissions test
- Likely to fail
- Parts involved
- Egr Cooler Coolant Pump
Related codes
- P24D1Particulate Matter Sensor Regeneration Incomplete
- P24D2Reductant Heater A Sense Circuit
- P24D3Reductant Heater B Sense Circuit
- P24D5EVAP System Pressure Sensor or Switch B Circuit
- P24D6EVAP System Pressure Sensor or Switch B Circuit Range or Performance
- P24D7EVAP System Pressure Sensor or Switch B Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.