How do I fix code P0402 (EGR)

[greg0145]

Code P0402 (Flow Excessive) has been showing up with increasing frequency and today P0401 (Flow Insufficient) came up for the first time. What are some common problems and solutions for Exhaust Gas Recirculation Flow errors?

 

[Earl43P]

Wandering over here: http://www.tomco-inc.com/Tech_Tips/ttt36.pdf should get you started.

Most times it's a bad DPFE, but it could be carbon clogged passages, split hoses, bad solenoid, etc. Very rarely is it the actual EGR valve itself.