96 TALON ESI Idleing problem please help

Ok guy I just bought my frst Talon. Its a 1996 Esi model 2.0L it only has 84,000 miles on it. I did everything changed oil,filter,air filter,pcv valve,plugs,wires and it still didn't fix the problem.When you first start the car it idels perfect sounds like it doesn't miss a beat, but as the engine gets warmer the idleing gets worse it gets so bad you can see the engine auctially vibrate. :banghead:
Can anyone give me some advice what might be the problem.
Thanks in advance