I hope someone can throw some light on this.
I have a 1996 (N plate) RS2000 with the original 2.0 Zetec engine.

When I first start it in the morning the engine runs really 'lumpy' and the revs seem to 'hunt' between 1000 and 1250 until the engine has been run for a little while. It only ever settles down to just under 1000 rpm once the engine is up to temperature, and the 'lumpiness' is still noticable after that.

Any ideas what could be wrong?

I need to arrange an oil change as I am not sure the correct oil was added at the last oil change (5W 30) and I don't think this is helping either.

Cheers, Roy