i currently have a obd2 97 civic ex and just purchased a straight-thru racing catilytic convertor. the cat that i purchased does not have a hole for the o2 sensor. would i be able to use the cat without the o2 sensor connected? will there be any problems that would come?

thanks in advance

 

You would probably get a check engine light for sure.

 

u probably would get a CEL code, or hell just tap a new hole for the sensor

 

You'll get a secondary O2 CEL. Ideally, you need to have another O2 sensor bung welded in.