Vibration issues 02GT Auto

I just got a 02 GT all stock with over 100k miles on it. I've had it only 3 days now....and notice a slight vibration up past 2k rpms.
I can put the car in park and rev the engine and feel it...so I know its not a driveshaft or rear end issue. Any help where to start would be great.
 
  • Sponsors (?)


It's slight vibration....and as the RPMs goes up the vibration stays steady till about 3k. Didn't notice any visable movement in the engine compartment. I drove it on the hwy yesterday for the first time since I got it....and noticed at 70 mph it's more noticable. But it's not a vibration that shakes the whole car....I just feel it in the seat.