M110 D jet revs up and down when cold

Hello all,
I have enjoyed this forum and learned some good information from it.
Now it is time to give something back. My W114 280E would rev up and down when idling in the warm up phase. It would start OK, start to rev up and down after half a minute then when warm it would idle well. Running was unaffected. I surmised that the cause was an air leak in a hose to the cold idle bypass valve. So I removed all of them. When I removed them the hose clamps felt snug. The hoses were in good condition. So I put everything back, making sure that the hose clamps were tight. Not too tight though. The problem disappeared after this. I can only assume one of the clamps was not tight enough. So if you have this problem and the hoses are in good condition don't rule out that the clamps might not be tight enough, or air is getting in some way.
Regards,
Lance Smart
From the lockdown capital of the world, Melbourne, Australia.

Hello Lance,
the problem is so often the wrong air,
good that we could help with the forum.
Hans-Jürgen