Engine Performance problem
1995 Rover 4 Series 4 cyl Front Wheel Drive Manual

hi! Can anyone please help me.i have a rover 416 si n reg. 1995.it can start one day, but not the next day, or i can drive it to the shops and it wont start again.also when i drive around locally, the car kangaroos then is okay again,but on long distances it kangaroos all the while, say 20 odd miles,and can guzzle about  £20 of petrol or more and cannot continue my journey. had to get breakdown to tow me back home.sometimes when idling the revs go up to 1500 rpm and sometimes tries to stall.Iknow there is alot of problems but i am now at my wits end with this car. thanks.