EGR question ?

Hi there this is a noob question , I got the chekc engine light come on and the error code show was P0400 which is the egr malfunction.

Now i was looking around and found out that there is the
EGR valve
EGR Bleed Filter
EGR Vaccum solenoid
EGR Valve gasket
EGR Valve Spacer plate


Do in need to replace all /some ? cofused ...
Please help
Thankx
-Reeve

check it! I had the same issue with my millenia. I took it to Pep Boys and I was told I need to replace the valve and solenoid. My check engine light comes on every now and then. If you go to MazdaMedic.com they may give you some other Ideas. I just sprayed some throttle bottle cleaner and appears to keep the light from come on.