Question

What is OBDII code P0400 on 1999 Nissan Maxima? what is the meaning of the code?

Answer 1

Hi there,

The code is for EGR function. It's indicating that the egr is closed and not working properly. Most of the time on the maxima it is due to the egr tube being plugged up. You can remove the tube and clean it out to resolve the problelm.