Moin-Moin u. Watte-Watte for our Berliner Hello friends a successful new year 20+20 for ALL. It is a Senator B Bauj. 87 . For some time already the engine speed fluctuates at cold start and always ran round as soon as it got warm. I recently renewed because of gasoline loss, new hoses at the distribution and also the injection nozzles. But now, I realize that the engine speed at minute intervals at idle suddenly after a quiet whistle slightly sc I can’t find this whistle. Could someone please tell me where this little whistle could come from and what it is at and where it is at. Had already searched for small animals in the engine compartment without results I did not have an OBD for an éventual error message. Greeting from France.