This is driving me nuts, 1995 Maxima, have replaced coils, fuel injectors, spark plugs, O2 sensors, EGR valve, all vacuum hoses, fuel filter, and others I can't remember at this time. The 1400 will appear and disapper but the 300, I can't resolve, any help out there?

 

what are these codes for?

 

300 is multiple misfire right? what type of plugs did you install?

What brand injectors did you use and coils did you use to replace the oem with?

 

The P0300 is a random/multiple misfire code. The P1400 is for the EGRC solenoid/valve.

 

when u changed the egr did u clean the tube? for the p300 did u check the compression of each cylinder