I'm not sure how to discribe the problem and yes I did try searching. I have recently noticed a "knocking" sound for the first few second when starting the engine. As part of a service visit they found and replaced broken engine mounting bolts and I thought that this must have been the source of the noise. It is not as loud but is still there. Does anyone have an idea on the source of this noise. I use only 93 octane fuel in a 2004 MT with 34,000 mi. Appreciate any help provided.

MH