Chrysler Repair: ENGINE STALLS CHRYSLER T&C 2005, powertrain control module, chrysler town and country

Question
I have a new 2005 3.8 6cyl Touring Chrysler Town and Country and the engine has stalled on three separate occasions.  Of course the engine cuts back on once the stalling occurs, but the dealership is unable to pick up any codes from the vehicle.  I think they are to the point where they are in disbelief and aren't doing much about it.  The stalling has occured approximately every 500 to 700 miles, has 2050 miles on it and has had one owner - myself.  With the first repair the dealership found a loose ground wire and replaced it; with the second repiar the dealership replaced the powertrain control module (I believe what is the computer), but my car stalled again while parked in my bank's teller line on 6/30.  I understand you do not have information on the latest cars, but perhaps you can lead me in the direction I need to go; we are taking vacation at the end of July, and I am sincerely concerned about driving this vehicle with my children in it.

Sincerely,

Makeda

Answer
Hi Makeda,
An intermittant stall is always a challenge. How quickly after the stall does it restart? It appears to be immediately from what you recounted. If there is no fault code noted by the powertrain control module (PCM) then the mechanic has no clue. It almost has to occur at the dealership, and even then if it restarted with the first try then you still wouldn't have a clue.
The one part that has the possibility of causing a no code stall is the autoshutdown relay. This relay is what provides power to the spark coil, the fuel pump, the oxygen sensors, the fuel injectors, and the spark coil. The relay is controlled by the PCM and if anything is unusual in the way the engine is running (or not running) the PCM disables the relay so as to prevent fuel and spark from being present to induce a fire in the unusual situation (like for example an accident). If it does the disablement, it leaves a code as to why. However if the relay does it by itself due to electrical misbehavior it won't set a code that can be read by many of the code readers, which might include even the dealer's.
The best way to self-diagnose such behavior is to become familiar with the sounds of one of the parts it controls, namely the fuel pump. When you first turn the ignition key to the run position (where the key sits after you start the car) listen for a brief (1 second or so) whirring sound coming from the rear of the car near the fuel tank. That is the sound of the fuel pump. You may have to leave the window or door open to hear it, or get someone else to turn the key while you stand near the rear to listen.
Then the next time it stalls, when you try to restart it, use the ignition key the same way: just turn it to run, and listen for the sound of the fuel pump. If you don't hear the pump then that likely means the relay is not responding properly which would explain a no start if you then move the key to the "start" position and it doesn't start. The relay might also correct itself just when you then move the key to the start position, and thus start right up.
But the failure to hear the fuel pump would be the easiest way for you to get a handle on this situation. Of course if the next time it stalls it won't restart then whoever analyzes the situation will find the cause of that, no doubt.
Roland