Truck popped the following codes on a trip a couple weekends ago - P0401 and, pending, P0424 with the CEL light (why I checked codes).

I cleared them, drove the truck hard for a bit, and since have not had the CEL.

Looks like the P0401 is related to the EGR. Im at 85,500 miles or so, the EGR was replaced around 25,000 miles.

Anything I should be aware of?

 

the cooler sometimes plugs up on these trucks unless you drive them hard.


there are some videos on it.

 

Are you sure it's P0424 and not P042E?

P042E - Exhaust Gas Recirculation (EGR) Control Stuck Open


Description: When the EGR setpoint is less than a specified threshold, the actual EGR position is greater than a specified threshold, and the EGR control limit is less than a specified limit, this DTC sets.
Possible Causes: Damaged EGR valve

Diagnostic Aids: The presence of this DTC may indicate that the vehicle is operating in derate mode and may experience a loss of power.
This DTC sets when the powertrain control module (PCM) detects a stuck EGR valve by detecting a position control deviation that exceeds a calibrated threshold.
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test W .


P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient Detected


Description: Estimated EGR percent is less than the minimum limit for the operating conditions. This DTC sets when the pressure ratio of the manifold absolute pressure (MAP) sensor signal and the exhaust pressure (EP) sensor signal across the EGR valve is not as expected.
Possible Causes: Aftermarket intake systems or exhaust systems
Restricted air flow (intake or exhaust)
Restricted EGR cooler
EGR valve position sensor bias
Exhaust pressure (EP) sensor bias
Manifold absolute pressure (MAP) sensor bias
Damaged EGR valve

Diagnostic Aids: The presence of this DTC may indicate that the vehicle is operating in derate mode and may experience a loss of power.
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test W .