Ok heres my problem.
installed pacesetter header and collector to rest of my exhaust>>> Dynomax resonator(22in) 2.25 piping to magnoflow muffler>>>No Cat. Installed bosch 15729 4 wire universal o2 into collector of new header, to replace stock 2 wire. Everything worked for a few days, now i get a P0420 code....Catalyst system efficiency below threshold (bank 1) So this brings good news and bad news. Good news my universal bosch o2 is working!!(i think) and It is detecting that i basically have no cat or it is not working properly. Should i just put in a high flow cat(85 bucks) or have the ecu reflashed?? what are my other choices??
get a highflow or a down stream o2 sim that should help ya
Would a down stream o2 sim bolt into the bung and plug into the harness like the stock one, or does it just plug into the harness and then i would have to plug the bung?? where can i find these??
hmmmm i tapped into the heater wires of my second/rear o2 sensor to heat my universal bosch header sensor, will the heat set work if i use this?
Ok, so I'm a bit confused...do you have both O2's installed (the precat one, in the collector on the header, and then one that would have been post cat, if you had a cat)? If so, something else you might try...
http://forums.clubrsx.com/showthread.php?t=296791
I realize that example isn't for our car, but it works the same (many platforms use this trick). Basically, you buy a couple spark plug anti-foulers, drill one out, screw that one onto the O2 sensor, screw the non-drilled one onto the drilled one, and then screw into the O2 bung. By moving the O2 sensor out of the direct flow of your exhaust, the computer will see less exhaust flow from the post-cat O2 sensor, which is exactly what it wants to see, and it should be happy.
Or just get a high flow cat installed...
