Engine Mechanical problem
1983 Mini Cooper 4 cyl Two Wheel Drive Manual 97.000 miles

Hi my engine revs every now and again it has been revving from 1 up to 2 and now it has started revving higher 1 - 3 im a bit worried as im not sure what it is. It sometimes does it when i start the engine up and sometimes not until ive driven it for a few minutes. I can happen at any time. My car hasnt had any mechanical problems at all and runs perfectly every day until these past few weeks.