C207 e350cdi engine hunting.

[landydave]

Hi. Hope someone can point me in the right direction. Infact any direction will do. I have a c207 e350cdi 2011. Absolutely love the car. However after a reliable 122,000 miles a problem has arisen that I cannot solve. The other day while parked at traffic lights she cut out. Almost like fuel starvation. After the 5th attempt it started and seemed to run fine. What I noticed was a slight hunting of the revs at any rev range. On further investigation I found that this is, i think, caused by the throttle body butterfly oscillating between open and closed while the revs are constant. Car starts fine, ticks over and revs well but always has this hunting. Can anyone point me in the right direction as I am stumped on this one. I do like to do my own maintenance and will have a go at anything once I have a direction.
Many thanks in advance.
Dave