What it means
The pump is electrically intact but does not deliver flow when commanded - typically a worn impeller or seized rotor.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The EGR cooler coolant pump moves coolant through the cooler so exhaust heat can be removed before the gas is recirculated. The control module checks whether the pump delivers the expected circulation when commanded; P24A8 means the electrical command can be present but pump performance is inadequate. A worn impeller, seized rotor, or restricted movement can leave the cooler short of coolant flow.
Common causes
Most likely first.
- Pump impeller worn or rotor seized
- Carbon or debris buildup preventing free movement
- Component wear with age - mechanical play
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
How to diagnose it
- Record freeze-frame data and review scan-tool pump command and any available pump-speed or coolant-temperature feedback to see when performance fell short.
- Check the coolant level and inspect the EGR cooler pump and hoses for leaks, kinks, blockage, or signs of overheating.
- Inspect the pump connector and wiring for damage that could reduce power to the pump despite an intact circuit.
- Command the pump with a scan tool, if supported, and check whether it runs and whether coolant circulation is evident using the vehicle's specified procedure.
- If the electrical supply and coolant path are sound, remove and inspect the pump for a seized rotor, worn impeller, or excessive mechanical play.
Common fixes
- Restore the coolant level and repair any leak in the pump circuit.
- Clear a kink or obstruction in the EGR cooler pump coolant path.
- Repair poor pump power, ground, or connector connections.
- Replace a pump with a seized rotor, worn impeller, or excessive play.
Can I keep driving?
Limit heavy-load driving because inadequate EGR cooler flow can raise cooler temperatures and contribute to knocking, hesitation, or power loss. Stop if the engine overheats or knocking becomes severe.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.