Several things could cause that. You could have a vacuum leak or it could be a sensor that's telling you your vehicle the wrong air/fuel mixture or even cause the timing to be off.
Crank the engine and listen for any air leaks. If you do hear one then it's going to be something in your evaporative gases system. Check the hose connections and hoses for any breaks, cracks.
Next, check your E.G.R valve. You do this by letting your vehicle warm up and then unplug the vacuum from it. Plug the hole and if it doesn't act any different then your E.G.R. valve will need to be replaced.
When is the last time you checked your O2 sensor or had the cap and rotor, plugs, or plug wires checked and replaced as this could be the culprit as well.
You also might have a bad (I don't know if this year has them) camshaft or crankshaft positioning sensor though I'm going to say that this is probably not it and it has something to do with your vacuum or vacuum connected sensors like your E.G.R. or M.A.F. or M.A.P sensor.
