2001 Limited Left Front Noise When Cold

I've got a 2001 limited with 16,000 miles. When cold there is, what sounds kinda like a leaky exhaust noise. It gets louder as you accelerate. When you let of of the gas at any speed it stops. After drivng for about 10 miles or so the noise diminished to ALMOST normal. Does anyone have an idea what this could be.

Thanks for your help! Four Z's

Check the rubber grommet where your transmission shifter cable goes through the firewall. My 02 did that and the grommet had popped out of its hole at the bottom. I popped it back in and its quiet now.