P0401 Low EGR Flow. Valve OK, stuck Solenoid replaced How to trouble shoot? on 1996 Ford Ranger

P0401 code. (Actually a Mazda B2300) Checked EGR Valve and replaced stuck modulating solenoid. Vac lines checked good too. What should I be checking, and how? Vehicle runs fine except for the light, but emissions test due at end of month.

by in Crawfordville, FL on December 04, 2012
1 answer
ANSWER by on December 04, 2012
possibly clogged EGR passages.