P0400 is rated as medium severity. Schedule service — affects performance or emissions.

P0400

EGR Flow Malfunction

Q: What does code P0400 mean?

EGR Flow Malfunction: The Exhaust Gas Recirculation system flow is outside its expected range.

Powertrain Code · Medium

What does P0400 mean?

The Exhaust Gas Recirculation system flow is outside its expected range.

System: EGR System

P0400 is a powertrain diagnostic trouble code indicating egr flow malfunction. This code is classified as medium severity, which means: schedule service — affects performance or emissions.

Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your vehicle.