Hi all,

In summary, I have a rattling 3rd cat, and im going be doing a stage 3 and installing a dynomax res. Should I remove the 3rd cat?

Getting in my 12" dynomax resonator tomorrow. Just did a mid muff delete last week and going to skip stage 2 for the price. Exhaust is actually slightly audible, but barely...in fact, my dad (who owned it and put 100,000km over the past 6 years couldnt even tell anything was done to it. he still doesnt know lol). The stage 3 will be plenty for me and dont want anything louder. Will a cat delete make it scream?

My 3rd cat (last cat before the resonator) rattles. it rattled around the 1800RPM mark stock. pretty annoying. I did the mid muff delete, and for a few minutes it rattled like hell when reversing, still does to an extent. It sounds like theres something loose inside (rusty bolt fell off?). it now only rattles when reversing basically, around the 800RPM range. Prefer this to rattles every time i accelerated before. Obviously, im unsure where the resonance will be and what RPM this dynomax resonator install will cause rattles. i will be fuming if its somewhere like 1500 rpm or higher up because i will be hearing it all the time. Not going to get a new cat becuase its pricey, so thinking of removing it. J pipe will be too expensive for me. After this install, i will be done with exhaust mods.

Will i get a check engine light if i remove the 3rd cat? My exhaust guy said it would, but doesnt look like it will. Would i be able to take a look inside my cat and see if there something loose to be attached/removed?

FYI if someone is in my position, i have read here that 3rd cat delete + the 12" dynomax res will cause rasp around the 3k mark. Using a 18" dynomax wont.

 

No, you won't see a CEL after removing the 3rd catalyst. But it will fail a visual inspection if you have one.

Yes, it will be louder and more buzzy sounding.

Try removing it and see if the rattle goes away or if the exhaust is too loud.

 

removing it = cutting it off right? Didn’t have enough time to see if it was bolted on each end.
funny enough the top half of the housing is shiny metal, the bottom half is browned up, but not rusty. Of course it’s expected, but the 2 literal halves are in different condition with no transition between them.

 

No cutting of any piping is needed. Just un-bolt it. That way, its reversible.