I have a similar issue, but different outcome. When I accelerate as you do, not slowly, gently, but quickly, in otherwords "under a load" I hear an anoying whistling sound. Not when in park and press on gass, and not so much under a slow, gentle acceleration. Just when accelerating hard while driving. I am curious if these could be related.
SPONSORED LINKS
Sunday, June 6th, 2010 AT 3:10 AM