I would check the following in this order:

Plug Wires
Fuel Filter
PCV Valve
Distributor Cap/Rotor

Is your Check Engine light on? You can also reprogram
your ECU buy disconnecting the battery (make sure you have
your antitheft radio code if appicable) for 10-20 minutes.
Then rehook it up. It may fix it, or it may be OK for a
while and go back, then you know you have a sensor prob'
somewhere.

t