Idle revs fluctuation

[ogs]

Ok this is a wierd one was wondering if anyone else had this problem. I have a 2.0l 190e and when in traffic the idle revs are at 2000rpm if I tap the accelorator they go back to normal and this only seems to happen in traffic when crawling along, when driving normally its fine when I stop, any one know what could be the cause?

 

[BlackC55]

Stick throttle mechanism?

 

[ogs]

possibly, I'll give it a once over, thanks!

 

[television]

One of the 2 return springs has a habit of breaking

 

[Dieselman]

I'd go for return spring also.