Yeah I thought about the cat, If the cat is clogged then it's not showing any of the normal signs such as low vacuum or unusual O2 sensor readings, but I suppose it's a possibility. I honestly don't know how to be sure, I may have the local muffler shop take a look, they say they can tell if it's clogged.

The radiator used in today's road tests is actually new, the old one was 7 years old and had some questionable deposits on the inside, so I went ahead and got a new one, even though it turns out the old one still works fine. I guess I have a spare now.

Everet I know you have a real temperature sensor, can you (and anyone else who has one) give me some examples of temperatures your Sporty runs at under normal driving conditions, or freeway, or going up a hill, etc? Anything, just to get an idea of what kind of temperatures are normal for a Sportage...