Ok, I posted awhile back about my girlfriends 1998 Civic EX with a full exhaust and an Ebay "high flow cat" well I welded a bung on the cat and put an O2 sensor in it, but I got an P0420 code(efficiency below threshold) I noticed that I can't buy a casper O2 simulator anymore, so I heard about on that you screw into the cat and then screw the O2 sensor into it. Has anybody heard about this kind? and also will it work for me??


Thanks

 

Efficiency below threshold usually points to a bad cat (or in your case no cat?). I don't know anything about O2 simulators but they are probably illegal and i don't think the ~10 HP is worth the trouble.

 

If it were up to me I would just throw in a new high flow cat, but she really likes the sound of her car and wants to keep that sound, so ai have to figure a way around it