I was wondering when is it recommended to replace the EGR valve? I've had mine cleaned multiple times but the P0401 code keeps coming back. Does that mean I should replace the EGR or should I try something else first? Thanks.

did you clean the egr port?

see the FAQ's for more info.

I have always had a mechanic clean it so I'm not sure if he did that or not. It seems to be fine for about 3K miles after he cleans it. I will try to follow the directions in the FAQ and try to clean it myself this time. Thanks for the information.