engine cuts out at idle - e36

["Noordien, Igshaan" <in1@xxxxxxxxxxxx>]

Hi folks
My e36 320 (small six) is due for a major service (260 000 km on odo)
which I'll be tackling myself.
Yesterday driving home from work it started to cut out everytime I
coasted to a stop at a traffic light or in bumper to bumper traffic.
The revs would go right down to below 500 and cut out; sometimes it
would kick back up to 700rpms and sometimes it would idle normally.
Also when it does idle it feels very rough - as though there is a slight
rocking motion coming from the engine. Any ideas what this could be -
I'd like to deal with it when I do the service.

TIA

Igshaan
'92 320 (e36, small six)
Cape Town 
South Africa 

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