When I press on the gas pedal it makes a clunking and a really bad vibration sound. The sound goes away when I release the gas pedal but it will even make the sound when I have it in cruise control. It sounds like its coming from under the hood and it doesn't do it every time I press the gas just every now and then while I'm driving. I just got an oil change and tire rotation yesterday and its still making the noise. It seems like its getting worse.