A P0401 DTC (exhaust gas recirculation flow insufficient) is ...

[RYAN BANYAN]

A P0401 DTC (exhaust gas recirculation flow insufficient) is being discussed. Technician A says that a defective EGR valve could be the cause. Technician B says that clogged EGR passages could be the cause. Which technician is correct?
◦ Technician A only
◦ Technician B only
◦ Both technicians A and B
◦ Neither technician A nor B

[Missbam101]

Both technicians A and B

[RYAN BANYAN]

Thanks for the timely response, appreciate it

[LegendaryAnswers]

Wow, this really help