Ok I'm still driving my 97 Mitsubishi Eclipse Spyder GST

I know it needs a new CAT bad, its clogged without any doubt. My question though:

I have a check engine light coming on as soon as the car start, it's a random mis-fire on all clyinders.

I also have low idle rpms. In neutral, my rpms are around 350 to 300 range.

I'm getting the CAT replaced in 2 days, but I was wondering..... Could the CAT be causing my other problems? I've read around and I keep reading things going back and forth...

CATs cause mis-fires...

Mis-fires cause bad CATs.....

Any ideas?

I'm just wondering if I should have the shop look at the misfires before switching the CAT out.... Limited on cash flow at the moment and I'm trying to set my priorities.

Thanks all!

Joe