Honda Accord 92 transmission

Buy a Honda Accord 92 Motor 2.2L! ... but the transmission puts the change when you want! ... but if I release the accelerator little if it puts the next change while not! .. although slowly berry puts the changes at 3 thousand rpm ... the transmission does not work? or what can have! ... also when the car reaches its normal temperature, the revolutions go down and begin to tremble but when I put it neutral the revolutions rise as to 1200 and so they remain! ...
thank you very much