Originally Posted by My new weekend job

Hi onehundred80 thanks for your input, I did a lot of research including searching for Mercedes SLK R170 faults, a number of people said they had cured a similar noise by replacing this part, there are a lot for sale on Ebay etc suggesting they are regularly bought, this is probably because they contain a rubber diaphragm which fails causing a leak, they're an inexpensive part so a good place to start in my opinion. Please can you provide some more details of the valve you've mentioned so I can check mine. As you seem to have a lot of experience of these cars please could you also let me know where I can get replacement vacuum lines, connectors and valves? or what the specifications or part numbers are? Many thanks in advance

I have a good recording of the noise but there didn't seem to be a way of posting the file for other people to listen to, I tried asking the forum administrators if this was possible but haven't had a reply yet.