hi all just a quick question,how often does the cat on the z22se need replacing as i was considering getting one as my car is hesitant upto 3000rpm and was thinking that the lack of power was because of a blockage but just been searching for a price and even on ebay your looking atleast 250-300 squids,so now trying to rule out the cat instead of replacing.also had the egr off today didnt look too bad but couldnt find a thread on how to clean my particular egr so just stuck it back on