is there an 02 sensor in the cat in a 94 z28? Im going to put a cutout on my car but i don't know whether or not to put it before or after the cat. If there is an 02 sensor in my cat would it cause it to run lean?

 

I think you have an O2 after the cat, im not sure though. My 95 has 2 O2's, both are in the Y pipe BEFORE the cat, but I think yours is different.

A bad O2 will usually cause a car to run rich, but I think it can also cause it to run lean.

 

94 is OBD1 so no you don,t have an O2 sensor after the cat.
OBD2 cars (96 and up) have after cat 02s.

 

The 02s' are located in the y-pipe before the cat. As for a cutout it will be a tight fit before the cat, most of the people install the cutout before the axle.

Vinny