How do I know if my car is california specs or not?

 

you should have 4 sensor's on the front part of the motor. Then it should say something about cali emissions under your hood. You should have this weird looking bell thing called the Swish valve by the manifold where the knock sensor is. Ahh i think that's it for checking. Also cali-spec has pre-cats in the headers and not the y-pipe.

Edit- Since your a 99 i'm 99.9% sure your a cali-spec.

 

i'm about to buy a warpspeed y-pipe for my 95....it says on the auction it's for cali. spec maximas...so what do u think? remember i'm new to the whole Nissan thing....especially maximas

 

95-98 fed spec and cali spec y pipes are the same. they are actually f shaped. the 99+ cali spec are more y shaped because they are missing the front up pipe (stock cat stays in place).