The engine on my 1500 stalls when coasting down to a stop. The truck recently threw a code for MAP sensor. So Ireplaced the MAP sensor and TPS and it seems to be worse than before. While I had the throttle body off, I cleaned it and checked all the lines for vacuum leaks.

When coasting to a stop, the RPMS on the tach drop to almost zero, then the engine stalls. I can catch it a few times dropping to almost zero, the engine hesitates, then the RPMS jump back to where they should be and the engine does not stall.

When the engine does stall, if I shift it into Neutral and turn the key, it starts fine with no hessitation.

 

Does it only stall when the motor is warm? It did it to me when it was warm, coming to a stop and when I shiftedfrom Park to Reverse at low idle. It was the Idle Air control valve. It is mounted on the back of the throttle body with 2 screws. Cost around $40 at autozone.

 

Yeah, seems like you went in the wrong direction with your $$$.
IAC would seem to be the culprit. As the RPM's come down so too does the idle speed and if your idle air passage,and/or controller is not up to snuff, Adios to your idle!...
...STALL

 

It was the IAC, I changed it last night and it works fine now. I replaced the MAP and TPS because the computer threw a code for the MAP. I got 206k out of the originals so I figured changing them now would be a good idea. I did not know about the IAC or I would have changed it at the same time.

I also now know to take off the IAC and clean it every now and then. There was 11 years of crud in the IAC passageway.