Help: 1995 Chrylser Cirrus: bizaare behavior

This is a follow up on an ongoing troubleshooting project on my daughters car.
1995 Chrysler Cirrus Lx, 2.5L V6, automatic
    Recent history:
car starts and stalls intermittently. Sometimes when cold, sometimes when warmed up. Various codes were set from time to time but not always. Mostly: TPS, IAT, MAP related.
    Procedures so far:
wiggle test many spots in the wiring harness trying to get the problem to occur and stick. no luck.
End-to end wiring checks on from PCM socket to TPS, IAT, ECT, MAP. IAC, etc. All good.
Pulled PCM connectors and cleaned female ends, applied small dab of dielectric grease to each. reassembles.
run voltage tests (cold engine) on IAT, ECT, and MAP. good. Them test again on warm engine. all within spec.
    Current car status:
Ran car for three days. no codes. Still stalls occasionally. However, a new symptom has surfaced: sit idling in park for 15-20 minutes. The engine will accelerate to 200-2500 rpm's, drop back down to almost to a stall, then repeat high rpm's again. It did this several time over a 2 minute person.
    Current personal status:
I am going out of my mind trying to track down this problem! The only thing I can't test effectively is the IAC motor.
Have any of you guys ever experienced this problem before?
Thanks again of the help in the past.
Bill
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Today a new crop of codes popped up:
71, 23, 33
Manpower: do I start looking for a PCM?

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wrote:

Those are not good Chrysler fault codes, you really need a scanner to see what is going on. to see what the values of the sensors are doing when the problem occurs

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wrote:

kinds of havoc and very hard to find unless it gets to the point that it will not start, then it is found easily. If I were to tell you to take a pot shot at fixing it I would say replace the crank sensor.
Glenn Beasley Chrysler tech
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Glen,
These codes are now set (retrieved by counting the MIL flashes): 71 - PCN output voltage low 33 - A/C clutch relay open or shorted 23 - IAT voltage out of normal range
I disconnected the battery (neg. on shock tower) and the codes came back.
Bill

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Glen,
These codes are now set (retrieved by counting the MIL flashes): 71 - PCN output voltage low 33 - A/C clutch relay open or shorted 23 - IAT voltage out of normal range
I disconnected the battery (neg. on shock tower) and the codes came back.
And one more thing: I did previously notice that the rad fans would come on sporadically at inappropriate times, like when the engine was cold.
Bill

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wrote:

Normally if you coolant fan comes on for no apparent reason it may be due to an open coolant temp sensor circuit, it is the default setting for the PCM, If you were to cut either wire on the circuit or disconnect it the fan turns on. But since you have no coolant temp code I couldn't answer that with out seeing the values. Pin 43 is the ground terminal for the IAT sensor, it is spliced off that and feeds the other sensor grounds.
Bill give me a good e mail address
Glenn Beasley Chrysler tech
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wrote:

sensor gets shorted out it will cause the 5 volt supply to short out. Disconnect the connector and drive the vehicle to see if the problem still occurs
Glenn Beasley Chrysler Tech
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