My 2000 volvo S40 makes kind of a whistling/rattling noise near the passenger rear side and this noise is very intermittent. Usually i don't have the noise when i go to have it checked out. Whenever there is this noise it seems to be more prominent when going at lower sppeds on roads that are not the best and have some bumps. I just can't seem to understand what this could be.

Any insight as to what this could be or any troubleshooting advise is appreciated

thanks in advance

 

have the tire checked out....very broad topic, you need more detail for a better answer