My mechanic has told me that the rattle from my cats is loose honeycomb material breaking up. I am experiencing a loss in power as well. Should I look into having this replaced through the 80k cat warranty, or should I just upgrade or replace with alternative. Also, I would like some tips on affordable performance upgrades that are out there. Cheers.

 

Depends on what you really want. If the cat is bad under 80k miles they should replace it for free (youll have to pay a diagnostic fee though=(~$95).
If you have a 1.8t then a test pipe would give you some gains but isnt good if you have state emissions tests. You can get one for about $145.
Please list engine type/year when asking tech ?'s.

 

I agree!