Chrysler Repair: 2.5L V-6 hesistates when accelerating from 0 mph., throttle position sensor, vacuum leaks

Question
HI
We have had this car to many different mechanic and no one can figure it out. It has a bad hesitation just of idle when accelerating. It doesn't miss if you rev it up slowly or accelerate above 1500 RPM. It just had a full tune up, new intake gaskets, new map sensor because it failed in our testing. It has no vacuum leaks, the EGR has been tested and works perfect, the injectors have been flushed, and the cat has been checked. We also had the fuel trim check. I am completely confused over what to do next. The only things we have not checked or replaced are the cam sensor, the crank position and the PCM. What do you suggest.  

Answer
Hi Kenton,
It sounds like you have covered every possibility but I have three more to consider: the throttle position sensor. It could have a very slight discontinuity in the variable resistive surface near the closed throttle position. You could measure that with an ohmmeter across the middle and either outside contact of the plug. Another possibility is that the throttle body butterfly valve plate is cruddy, particularly check the rear surface, or that the idle by-pass channel is parially occluded, either of which would cause a transitory micxture mismatch when you begin to open the valve. So those are a couple of no-cost measures to try. One other: check the vacuum lines for the possibility of a crack at the nipple attachment points. Some times as the engine rocks slightly in response to being accelerated it could cause a crack to open up momentarily in such a fitting. Use the underhood sticker as a roadmap to check all the lines.
I assume that you have read the PCM memory for fault codes. Please let me know if any of those ideas help.
Roland