1992 Plymouth Voyager Jerking and High RPM's

Hi, I have a 1992 Plymouth Grand Voyager, and I have a few problems like, when the engine is warm while driving 60-80 km/h the engine light suddenly appears and the engine starts to loose power for a few seconds and get's it back again. It will keep doing this unless I slow down to 60 km/h. If I shut the van off hot and come back 10 minutes later, I start the motor and the engine light shows up again. It shifts fine into drive, but once I am going it rev's up to 4500 rpm before it shifts into second, and that is accelerating really gently. Once it hits second it will be at about 3000 rpm at 60 km/h and will rev up to 4500 rpm again before it shifts again. It does this in every gear. Also, when it's downshifting it will downshift a gear and rev high and soon as it downshifts, which causes the van to jerk really hard and you can hear your tires lock up for about half a second. After I park the van for about 4 hours and start it up, the engine light is gone and it runs fine until the engine is hot again then it does the same thing as I described before. I am wondering if you guys would have any answers? Thank You