I have a unique problem... my P0420 code isn’t coming back on... I have a test pipe in my S2 and the check engine light has always been on due to no cat and what not. I recently saw I had another code that required an intake solenoid. I fixed the issue cleared, the codes but the P0420 codes haven’t come back? I don’t have the 02 sensor plugged in and there’s no converter... shouldn’t I have these codes?

 

p0420 requires the sensor to exist. If there's no sensor plugged in you should get another code or two for O2 sensor heater circuit voltage low and others. They may take a drive cycle or two to set.