Thanks for the replies. Took it to dealer service for a check. Day before was buzzing like crazy, like I said around 2100-2200 RPM. Could not duplicate at dealer. I have bought 4 cars from this dealership in the last 5 years. They are one of the good ones, always go out of their way to address my concerns. They looked the car over and did find a bolt loose on a heat shield under the car. Like I said couldn't get it buzz that day. A week goes by all is well and then it's back, but only for a day. Hasn't done it since. It appears that it is also outside temp related. The day before I took it to dealer was a warmer day ~46 F. The day I went to dealer was ~36. It stayed cold after that for a week and the next day that it warmed back up is the day it started again. It has been cold since and no buzz. Go Figure. Talked with the tech at Ford and we decided that there is nothing to do but wait till it warms up again in the spring and see what happens. One reply talked about a loose heat shield and I think that it's something like that. There is another heat shield up higher than the one the tech tightened that seems sorta floppy to me. I may try my hand at tightening that one if the weather warms up for a day and the pedal buzzing returns. Again thanks for the replies.