bigmike_ws6

my cats are under warranty..however they said before they replace them they have to do a 65$ inspection to be sure they need to be replaced...is there anyway i can check them before hand so i can be sure theyre bad so i dont waiste the 65$ on nothing?? ..as of now im noticing a loss of power, and slightly low mpg...not sure on fault codes.. ..does the cat. cleaner stuff work??

TransAm_00

iTrader: (1)

Very easy,,, pull them off and throw them in the garbage.

2001NBMZ28

Normally bad cats are going to throw efficiency codes - P0420 (driver) and P0430 (passenger). If no code(s) doubt they'll replace them. SES on?

theinstag8r

iTrader: (3)

are one or both of your cats making noise. that's possibly from them falling apart on the inside, dealers can check for codes from the pcm and actually run tests with the car running to determine if it's performing up to par... i don't think there is a surefire way for you to check them

theinstag8r

iTrader: (3)

AND put on some nice headers

98Z28MASS

iTrader: (6)

To check your cats, simply take a crowbar/metal rod and repeatedly/forcefully push the crowbar/metal rod into the catalytic converter until you see all the packing material come out. Repeat this method on your other catalytic converter, bolt the y-pipe back up, and enjoy!

bigmike_ws6

lol right..idk my buddy took his cats out and if gave off the nastiest raspy sound..plus mine dont have flanges so id have to cut/weld them..but ill prolly just leave them on and maybe use a cleaner or something..

98Z28MASS

iTrader: (6)

Haha i hera ya man, just giving ya a tough time. You can def gut the cats on the stock y-pipe. Just unbolt it from the exhaust manifolds and the catback and you can get at them and hollow them out, but if thats not what your looking to do then just check for a rattle. If it sounds like you have marbles in your cats under acceleration then they are gone. I dunno how to tell if they are clogged but when my buddies cats blew out on him it made a nasty rattling noise in the cat due to the packing material blowing out.

rich Z

I have heard that at night they would glow red if bad. Another way is to hookup a vacuum gauge to the manifold and at idle slowly rev the motor up to 3k rpm. If the vacuum reading goes up or stays the same as it was at idle then the cats aren't clogged. If the vacuum goes down there clogged.

618HAWK

iTrader: (361)

I know there is a temp test that can be done. Along with a pressure check that can be done by pulling the o2,s and reading the inlet pressure vs the outlet pressure. Will require some test equipment though. Might call a good exhaust shop in your area that might be able to tell you a bit more.

A lot to deal with, probaly why most just get rid of them, or gut them.