I am taking my car in tomorrow to get the catalytic converter replaced with a magnaflow high-flo one. I want to also get the EGR cleaned out, I've been reading here and there about it, and my mileage isn't 100% of what it used to be, but it'* still kinda close. I just figured while it'* in, why not....what should I tell the mechanic or what should I know, like how do you go about cleaning it normally? I've been told by a friend that when I floor my car a little black smoke comes out, kinda like a high performance ricer, it'* just a puff when you initially floor it, so someone told me that means it'* running a tiny bit rich? And that the EGR could do that if dirty..... Someone help here on how to clean it, and such....

The way I clean them is with carb cleaners and a small wire brush. A little black smoke when you nail it is normal. Thats carbon in the motor getting burnt up.

Same way works good for me too.

Be careful when you decide to clean it. They will stay hot for a long time after the car has been shut down.