Whenever I slow down and then dip the clutch as I am stopping, or when I actually stop, the revs needle just bounces between about 300 and 1000 revs for a few seconds before settling down to idle at around 7-800.
Also, when slowing down from a slow speed (like when stuck in traffic etc) and the revs are bouncing between 300-1000 as described above, the brake pedal cushions hard and soft - similar to when braking hard where the abs coaxes the car to a stop rather than locking up.
It is very weird, and has started only 2 days after getting it back from having a new alternator fitted (the car was sat in the garage for 6 days without moving - the longest its gone without being started for at least the 2 years I've owned it).
Anyone got any ideas as to what could be wrong??