My 92' ES300 is lossing power when I climbing a 20 degree or bigger angle's slope. I accelerate it, but seems no response from the engine and the car won't move. If I pedal the accelerate to the end, I can feel something shaking from the bottom of the engine and the engine will cut off sometimes. Does anyone have an idea for what is going on? Possible areas: spark, transmission or exhaust?

knacked gearbox if its auto or bad clutch if its a manual

Start with why the engine is having trouble.

Bad spark plugs / rotor&cap / wires
Vacuum leak
Wrong ignition timing
Plugged cat
Incorrect amount of fuel
Low compression


Check in that order.
Don't replace the wires with generic crap. If they have damage, spend the big money for more OEM Toyota wires, or higher quality aftermarket wires. (Vitek / Magnacore)