1990 Dodge Caravan Transmission

If it started giving you problems on the first start right after you replaced the switch you may have blown a fuse somewhere either inside where the fuse panel is or in the engine compartment. Check those two locations. See the section called 'first things to check' in the menu section, it explains everything about testing the fuses. OK John.

Checked fuses Alll fine... Started van Put in gear..It goes into drive and makes a weird noise. Then when you stop or trun a corner the transmission is then in Neutral gear. Shifting the shifter in all gears does nothing. After putting it in park and waiting up to 5 mins or so shifting then it goes into a gear be it rev or drive.All gears then work and the noise is back..While noise is gone...No gears work..Noise seams to be coming from transmission area... ?????

I don't think your work on the key cylinder was the reason. Have you checked the transmissions fluid level, and do you remember if the filter was replaced yet, or was the transmission ever repaired?
It sounds like you may be losing hydraulic pressure. As your turning or running it the filter may be getting clogged or its level may be low. It may have a leak. This wouls explain the VSS also. The VSS is a speed sensor the speedometer signal uses, in 1990. If you have had no transmission problems until now you have done very well. The early transmissions were a problem. You have many miles. It may need a service but the noise could be a number of things, the torque converter or the pump may be noisey. Sometimes adding fluid may quiet it, but It has very high mileage. A good transmission though. It was first used in late 1988. ^04 was the name that Chrysler called it. Check its fluid, or for leaks. OK?