LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Geo >> 1996 >> Prizm Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Circuit Tests >> DTC P0401 - EGR Flow Insufficient >> Diagnostic Aids
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Diagnostic Aids

Check for a stuck MAP sensor value. Check EGR valve for plugged passages or a stuck closed condition. An intermittent condition may be caused by poor connection, rubbed-through insulation, or a broken wire inside insulation. Check PCM harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, or poor terminal-to-wire connections before component replacement.