Is this considered a VACUUM Leak? Egr Valve Leak
Cleaning dirty EGR valve is easy. A dirty and clogged EGR valve can cause P0400, P0401 etc. A very quick short on how to clean Symptoms of a bad EGR cooler How to Diagnose a bad EGR Cooler on Cummins ISX How To Tell If Your EGR Is Faulty - Common EGR Symptoms & Problems. The valve was not seating properly anymore and was leaking into the intake in a "closed" position. It has some debris between the ...