i have a 97 z28 camaro. it has 152xxx miles on it. recently ive noticed a rotten egg smell and gas smell in my car but not all the time. figured its my cat. i also just replaced my fuel pump so before i started jumping to conclusions i figured id ask around. also thought when the cat goes out you lose power and my car is running great and no engine lights are on.

any input would be great

 

Depends how the cat is failing. If the substrate is crumbling, it will break up and blow the pieces out the exhaust. Probably won't lose power. If the substrate has overheated (typically due to a rich condition) and has melted, blocking off exhaust flow, its going to kill the power.

Your OBD-II 97 has after-cat O2 sensors to monitor the performance of the catalytic converters. If the SES light isn't on, and there are no codes, the cars should still be performing OK.

 

..i hear metal clunking around when i take off. thought it was my suspension, but guess that could be the inside of the cat. is it a problem to drive it like that?

 

If the cat is breaking up and blowing out through the exhaust, if enough of it collects in the muffler, it might block it.

No codes? Do you still have the after-cat sensors, or have they been replaced by "sims" or programmed out?

 

I'm going in tomorrow to have my 01 Z28s cat changed under the extended warranty on the cats. the SES light came on and threw the 0430 code and was verified by the chevy dealer. 2000 - 2002 5.7 liter camaro and firebird cats had an extended warranty for 120,000 miles or 10 years

 

crap. i think my check gauge lights are bad. not sure how to check the codes.. but now when i turn the key to accessories the check gauge light stays on long as a few others. but once i start the car every light stays off. so on your 2001 z28 did your cats stink? how did you conclude that you needed to check it out

 

it threw the 0430 code . the "service engine soon" light came on. Ive owned the car since new and the light has come on twice in 78,000 miles . i took it to auto zone and had the code read and posted it over on ls1.com . everyone there told me that was the cat code for the right side. went to the dealer and explained the situation . the dealer read the same code and NO OTHERS . came to the same conclusion and now the car is home with a NEW CAT and 0 dollars out of my pocket! but no smell no bad running or anything just the light. and if the light is on , no inspection in NY so those SES lights can be a pain in the ***, because the average shop has no clue on how to get them to stay off

 

a good way to get the light off is take the battery cables off. after once or tice it usually makes the light stay off. have did it before. i live in california, the smog laws are a pain in the *** here. wish my car was a little newer and could get new cats for nothing. i looked them up and they range from 250-500 for them without install since i need the new california smog legal cats. hate this state for this. cant even pump my car up!! =( lol thx for the help