OK i have the same problem as a few people with other forums except it is in a 99 avenger with a V6. I have replaced the TPS, the ECM and the IAC valve. I have also checked almost every other sensor in the area and basically torn down the throttle body to try and figure this out. The car ran fine forever until one day on the ride home from work it kind of bucked when i let off the gas going down a hill. after that i noticed it everyday. A few months later the car stalled going throgh a parking lot and has been a complete pain ever since. The last thing my mechanic did was remove the IAC weather it be the motor or the valve and place tape over it and test it. The car didn't stall at all. We then thought we figured out the mystery so we got the iac valve today and replaced it and the car didn't stall on him when he finished working on it or when he dropped it off to me. Then of course as soon as I leave work tonight to bring a buddy of mine home wouldn't you know it it stalls in front of his house....... Please help if you have any other ideas. I have read in other forums that it can be the CPS(crank possitioning sensor) but how would that work considering the car starts and idles fine and only stalls when accelleration stops, wouldn't a flaw in this sensor make the car run offf at all times???? Thanks again.. Please help!!!!!!!! I just got my car back today after a month and a week without it and it is back on the disabled list....

Also secondly as no one has posted earlier, but the car doesn't spit a code out or a check engine light. Another wierd thing is that the handheld computer, i think its an alldata? when plugged into the car while driving acts normal and reads all information but once the car starts to try to stall it goes blank like it isn't plugged in. wierd huh?....... The car doesn't always stall, if you drop it into Neutral and rev it up it will stay running and the compter pops back up on the screen of the hand-held. Nest the hand held is "unable to communicate with the EGR and the IAC, thus making us relace the IAC which temporarilly fixed the problem. Another wierd thing i noticed is that when accelerating now that this problem has come out is that when you take off it feels like you are holding the brakes at all times too. This makes me want to look into the transfer case modules, which in a sense could be slowing the motor on deceleration thus confusing the car by hitting the brakes from inside the tranny connections causeing the motor to bind up and shut off. Although this doesn't always happen....... And also yesterday on the highway, while trying to reset the computer with milage, the serpentine belt tore out. This car has it out for me...... Please help if anyone has any ideas or I may just have to bring it to dodge and have them rape me to probably not tell me anything.

Thanks for your time and please help if you can

Have your PCM, battery, and alternator checked. Have you noticed your battery light coming on at all? If the alldata is blanking out when it stalls, sounds to me like electrical power may have been interrupted. My car was doing that when my alternator regulator died and my laptop just stopped logging. The reason was that the ECU was starved for power because my battery was not getting charged...along with everything else, but since I drive a standard, it was literally getting push started since I was at speed and it finally stalled in front of my house.
Remember that spark has a lot to do with fuel burning and if it's low, so is the normal output of the motor. Also, the primary systems will have power diverted to them when battery power starts to go below 11.5volts. This also causes other secondary and minor systems to stop operating or just give bad readings.
The CPS would be the last thing to check, though, it's not impossible for it to cause the motor to act up it seems.
Anyway, check the alternator, battery, and PCM.

All are fine, for my car the part is the ECM instead of the PCM, that I replaced. The battery is less then a year old and still pushing just over 13v. The altenator tested possitive eventhough the serpentine belt is gone on the car, it just blew off the other day when i dropped it back off to dodge. so the altenator may be running behind due to the crappy serp belt. Secondly we just tried today removing the IAC and EGR and taping them off and driving the car, and it ran fine. So knowing that the IAC valve is new i'm gonna try to replace the EGR and see where that leads me.