I need a new cat on my 99 blazer and was wondering if the magnaflow cat is any good?

And if it will throw any codes?

 

This cat has been discussed numerous times. Try the 'search' function.

 

yes it will throw a code, i put a magna flow cat on my 96 4x4 gmc jimmy, and now its throwing a po420 code. i believe the code is a insufficant catilist code. i would go back to a stock cat.

 

I got a Magnaflow Cat on mine and it didn't throw any codes. Only reason why I got one is my stock one busted after so long (never had it changed since we got it) and after we got the new one put on it worked fine and made my glasspack sound even better. Only other problem was the fuel filter was clogged up and got that changed. After that whole ordeal it's been running like new and its got 153,000 miles on it. Purrs like a kitten

 

i deleted my pre cat and put the magna where the post cat was and threw p0420 (catalyst effeciency below threshold) but it made it alot louder

 

just got magnoflow cat on mine with no problems