1996 Chrysler Sebring car would not start

I could not get my car to start after driviing to work. I had it towed and the garage got it to start but it would only stay running at high RPM's. Now it will only accelerate slowly. If you push down too fast it cuts off. They admit they are guessing and it might be the distributor. This is a 2.5 V6 chrysler. Any ideas how to confirm or disprove their theory? Any recommendations would be appreciated. The PCM is not calling out any codes except oxy. sensor. They don't believe the catallytic converter is plugged. Help!!