I definitely believe you. I did put in a cat. Unfortunately since I was kind of anxious, I grabbed a OEM cat.
If you read through this thread, you'll notice that I was wanting to return the car to stock.
... I kinda changed my mind since then.
I also replaced the upstream, and down stream O2 sensors. The CEL has not returned.
If I kept a bit more calm, I would have used a nice performance cat, instead of the OEM. Oh well.
Also [MENTION=9500]danbfree[/MENTION], the first owner installed the catless downpipe, but also a obnoxious and annoying muffler-less exhaust with a big fat resonator tail pipe thing.
Going highway speed rattles my ears from the droning.
So ... problem solved?
I think I'm going to get one of those nice Milltek Exhausts, which apparently are quiet, but good for higher hp.
Actually, I'm building a list of upgrades, most of it is new brake rotors, cooling (mentioned in that supercharger thread).
Actually most of my upgrades this year will be brakes, engine mounts (not just RMM), suspension, and cooling / intake stuff and the exhaust pipes.
I'm not sure if that means a tune adjustment from the intake / exhaust, I haven't looked into that yet.
Eventually I'll make a big jump from the mostly stock setup to a X47R, or possibly even a VT330R, with meth / water injection.
Ill probably spray the exhaust stuff with that ceramic heat coating, and if it's safe, probably a coating of lime green spray paint (I don't know how that affects the ceramic stuff).
But that big upgrade is at least a year away.