I have a 1998 Mitsubishi Eclipse GS-T Spyder and I have 2 major problems that I've been having w/ it. The 1st problem is that my alternator/water power/power steering belt is consistently breaking. I'm going on my 3rd replacement w/ in the past 9 months. It starts out w/ a screeching noise coming from under the hood and then stopping. It seems to go away if I press down on the clutch. Sometimes it was last for a while, sometimes it lasts for a short period of time, and other times it doesn't happen at all. Can anyone tell me why this is happening? It happens to every belt I get, so obviously it can't be the belts.
My 2nd problem is that sometimes the engine doesn't want to give any power. I can press down on the gas, and the RPM's will stay the same and then the power will kick in. A while ago I brought it to a shop and the guy said that I would need a new air throttle body, so I don't know if that would play a part in that problem. The only thing I can think of is that the fuel injectors are really dirty and I need new spark plugs.
Any help to either or both of these questions as soon as possible would be greatly appreciated. Thanks!

You may have a pulley either out of line or has a gash in the ridges and is actually cutting the belts.

I can promise you that you don't need a whole new throttle body. If it sputters and then kicks in then you could have dirty injectors. If you slam the pedal and nothing happens for a second or two and then it kicks in, then I'm willing to bet the TPS is bad.

When you put the new belt on, check how tight it is. The screaching is a sign of too tight or lose. When you put a belt on you should be able to push it down about half an inch.

I am betting that you have a pulley out of alignment. Is your belt shredding or breaking? As for the throttlebody I don't see how it can go bad. Maybe your IAC and your TPS, but the Throttle body? WTF...