kugai

k got 2 problems in my trash can s14, my a/c been out for a while and i kind of want it back, so i was cleaning my car and i was checking on my engine and on the right side the a/c hose i think has a hole in it. im thinking its the silver hose its on the bottom of the hose what can i do to fix it. the hole is as wide and long as a pinky finger. and also my engine temp or oil gauge go crazy every time i accelerate usally goes down the C but i was told that it could be my sensor is busted, so if thats that case can someone tell me where the sensor is? thanks oh yeah the engine is KA24DE tyty everyone