× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network

P0400 Diagnostic Trouble Code Discussion for November 2005

Exhaust Gas Recirculation System Flow Malfunction

Note: This is a professional automotive technician's resource.
Vehicle Owners: If you are seeking an automotive repair professional to service your vehicle, visit the iATN Repair Shop Finder.

Trouble Ticket Help Requests for DTC P0400
Help Request Posted
1996 Subaru Legacy GT 2.5L Misfire, MIL Lamp on VIN: 4SEBG6851T
P0400: Insufficient EGR System Flow Detected. ... a P0304 misfire code. PO400 came first (we checked it when the light first came on and it was only code. We cleared and when they came back it had both stored. Found several posts indicating problems with the backpressure transducer and the filter on the p...
November 18, 2005
1999 Mazda Millenia 2.5L MIL Lamp on VIN: JM1TA221XX
P0400: EGR System Flow Malfunction. To date no parts have been replaced, but have manually checked EGR valve operation with a vacuum pump and verified integrity of all vacuum hoses and wire connections and wire harness routing. We are a GM shop and do not work on foreign cars often. Any help is ...
November 22, 2005