Quick Cat Question

[belo]

I searched first to no avail.

My cat blew out on my beater 02 protege when it was misfiring. The hangers now broken and its hitting the bracket and making a lot of noise. Going to bight the bullet and replace the cat (so i can pass inspection as well).

But...

Do i need to replace the pre-cat too? There's a good chance its also toast. I dont want to buy a new cat and have it go bad due to a bad pre-cat. Will I also need a new rear O2? Any way to know if it's bad or good other than trial and error? Only want to get under the car once and be done with it.

thanks in advance and happy holidays to all

 

[tweety2300]

there is no way to tell if your main (2nd) cat is bad or not the ecu will only tell you if the pre (1st) cat is good. if you notice the 2nd o2 sensor is behind the pre cat thus getting all of its readings only from it. there are a few ways you can fix it spend $1k from mazda and do it right. spend a couple hundred from ebay and have it last a couple months or do the non fouler trick and forget about it. the main cat should be good enough to pass a sniffer test. or do none of these and find a shaddy back woods inspection place like i do

 

[belo]

the 2nd cat is blown out. i looked at it. i would go with the non-fowler but the bracket is broke and i just figure the best thing to do is replace it. there's a magnaflow cat for $240 plus gaskets from advance autoparts...