Chrysler Repair: 04 Sebring Stalling, 4 digit numbers, autoparts store

Question
Roland,
I just recently had my 04 sebring in the shop to replace a timing belt that went.  Now after the shop did the work my car has been running rough when in overdrive or reverse or even stalling every so often when I'm sitting at a stop light.  It seems as before the work was done the car idled at 750 rpm.(or the 3rd dash from the bottom).  Now when I am I'm idling its between 500 and 750 and feels like its sputtering.  It seems to stall when it goes below 500 though.  Now I took it back to the shop that did the work and they seemed to give me the run around into saying it was the fuel injectors.  So they cleaned them out with a "special" chemical and they said it fixed it.  Well it didn't work.  
Was wondering if knew of any ideas that it might be.  I do have a small exhaust leak towards the front of my car if you think that might have anything to do with it.

Thanks

Answer
Hi Brad,
If the exhaust leak were before the catalytic converter or the converter itself it could cause a false reading of the downstream heated oxygen sensor which would modify the mixture, etc., etc. So that would be worth sealing up.
Try the ignition key to get any fault codes that the engine controller may have noticed:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if the mileage reading changes to show any fault codes which are 4-digit numbers preceded by a P. Then let me know what they are and we'll go from there. You also can often get a free fault code readout using a plug-in code reader at a nationwide autoparts store such as
Autozone. When you write back mention which size engine (L) you have.
Roland