Jeep Wrangler Sputters in Odd Way

I just got a 97 Jeep Wrangler hat starts fine but then proceedsto nearly stall out after it has been driven a short distance. After about 15 or 20 seconds the symptoms stop and it drives fine. Whiule the car is sputtering like its going to strall if I depress the clutch and rev the engine the car revs up just fine but re-engaging the clutch makes the car sputter agin until after the 15-20 second time period has passed. I am going to try the crankshaft position sensor to see if this does the trick but does anyone else have any suggestions?

Before throwing parts at it, have the fuel pressure tested.