Hello, I have a 1989 Chevy Z24 and I was just wondering if any of you guys would have any idea what could be the source of these various problems:

[1] When I take the car out and put it into drive, the engine stalls immediately. (This only happens in Drive, Reverse and Neutral both have no symptoms) If I floor the gas pedal, the engine will "return to life" and if I drive it for about 5 minutes, the problem will just disappear until I leave it sit for several hours and try to drive it again.

[2] At around 30mph when the car tries to change gears, it begins to hesitate and acts as if it does not want to change gears. It makes a loud rattling noise, just before it shifts up.

I suppose that's all the major issues I have at the moment. Thanks for any help/advice!
Alex~