Dodge Repair: 2002 Chrysler T&C 3.8L surging, spark plug wires, ngk plugs

Question
Surging: example steep downhill, throttle off, A/C off, 2nd gear. approx 1 second slight release, 1 second heavier engine braking; repeat. More pronounced than A/C cycle would be (if it weren't off). Is audible. Stops DH surging with ignition off.

Cyclic surging is also detectable under moderate to heavy acceleration or climbing and is audible as well (others feel this but may not hear). Latter surging is often accompanied by periodic "false shift" shutdown where engine backs out as if computer were about to order upshift but doesn't. Power resumes normally. Surging is similar to 2 second cycle but unpredicatable cycle duration on false shift.

A/C cycling is NOT the problem; although the feeling is not unlike an old York compressor cycling on a small engine.

Otherwise smooth idle, good power, no oil consumption, no check engine light, recent Bosch +2 plugs. Thousands of miles thus. Seems downhill occurence rules out fuel filter, TPS.  

Answer
Get rid of the Bosch +2.  As sad as it sounds chrysler's run best on crappy champion plugs or possibly a superceded NGK plugs.  RE14PLP5 is the champion number and 0.048 - 0.053 in. is the plug gap, I beleive this should also be on the vehicle emissions label under the hood.

There is a service bulletin that came out in 02 that describes the customer complaint as:
Engine Sag/Hesitation And/Or Closed Throttle Start Stall
It may or may not be accompanied by a DTC depending on vehicle.  The repair is to replace the TPS sensor, though I know you feel it's ok and I can't prove you wrong.

I would recomend replacing the plugs with the Champions.  Also, what's the history on the wires?  The early years of the most recent body style (RS/RG) had problems with the spark plug wires arcing where they leave the coil and meet the only bracket that holds them in place.  Look for a white haze kind of marking frequently with a darker section in the very middle.  You can buy a cheap plug wire seperator from a parts store or just swap the top and bottom plug wires in that holder.  That seemed to move them far enough for me.

Let me know how that sits with you and if you've got access to any kind of test equipment we might be able to check a few sensors.  
Doug