1991 Dodge Dakota engine stalls

I checked the ASD relay. The contacts looked good and the coil checked out at about 72 Ohms.
I replaced the relay anyway but the truck still stalls, no change.

The only engine code was 55. I think this code just means its the end of the codes. Right?

For the Hall sensor I uplugged it and tried to do resistance checks between the leads but could not get any values, probably because I have a digital multimeter. The diode setting did not give consistent readings.

With the sensor unplugged I did take voltage readings at the plug leading back to the engine controller with the key in on position. The wires from the senor are not color coded and the plugs did not have any labels either so I " œm not sure which pin is what but here are the readings and for lack of any better labels I will label the pins top, middle and bottom:
Top: 5v Middle: 9.1 V Bottom: 0 v. In all cases one lead of the meter was attached to chassis ground.

I did tap into the wiring from the sensor at the plug and monitored the voltage readings with the key on and engine stopped and also with the engine running. I tried to take reading while cranking the engine but could not get consistant readings, (the meter only updates about once per second so that might have been part of the problem)

Using the same labels as above, here are the readings:

Key on, engine stopped
Top: either less than.1v or about 4.9 v
Middle: 9.1 v
Bottom: 0 v

With engine running
Top: between 2.5 to 2.6 v
Middle: 9.1 v
Bottom: 0 v
I left the meter attached to the Top pin as I traveled down the road and it was consistant at 2.5 to 2.6 v and I did not notice any changes just before any of the times the engine died.
If there is still some possibility of the hall sensor being bad let me know and I will get a new one ordered.

The truck did something new today when I first started it. It started and then died within a few seconds. It did this about 5 times and then I noticed the check engine light flashing so I checked the codes and found 32 and 42. After that it started and ran for a while but still did its usual thing of dieing 4 or 5 times within the first 3 miles and then running ok after that.
Thanks,
Gary R