Just noticed this noise the other day, at first I thought it was a throw out bearing...kinda like a sqeaking. so I paid no attention. I had my hood open the other day, and noticed it was coming from the valve cover on the drivers side. now keep in mind it only does this between 1700 and 2100 rpms. doesnt do it at all under hard acceleration or at idle. So I took the valve cover off, and checked for loose rockers and cracked valve springs, but found nothing???it doesnt seem to affect performance, but it is very annoying. just wonder ing if anyone has experienced this before? I'm thinking one of the roller fulcrums on a rocker arm is bad, or if maybe that emissions valve right above the back of the valve cover is making this noise?