W202 C280 Running rough when warm?

I recently purchased a 94 C280 and am having a problem with it when the engine heats up. It's smooth as can be until I've been driving for 10 miles or so. Then it runs very rough at idle, but seems to smooth out while driving. I have a code on the computer for the air intake temperature sensor, and was wondering if this was the problem? I've noticed on the air intake there are two sensors...One by the air cleaner and one by the intake manifold. Which is the intake temp sensor? Also, can this maybe be cleaned off and it'll work or do I need to replace it?
OK, my wife just called me and said the car won't start! It's turning over fine but not catching at all. She says she smells gas in the engine compartment after turning it over, but it just won't start...Maybe a spark related problem with this whole engine running rough/not running at all thing? This is the first time it wouldn't restart after it ran rough!
PLEASE HELP!
Thanks for any help!
Adam.