Transmission not shifting, Console Guage(fuel & oil) problems ? connected

Maintenance/Repairs
1

Just bought a 1991 Chevy 5.7 v8 g20 Van (Beauville), Definite fixer upper.

  1. Had a transmission rebuild in 2010, maintained a transmission fluid leak afterwards until the church bought a replacement van and this one sat unused until now.

  2. Transmission isn’t shifting into gear faithfully. RPM’s go higher than they should when accelerating before it shifts which it doesn’t always do. Noted that if it rev’s high and you remove your foot from the gas then re-accelerate it will shift ~50% of the time into the next higher gear. Drove it on the highway but did not notice it shift at all after 50 mph.

  3. While driving on the highway, I hit 60 mph and noticed that if I drove any higher the oil pressure gauge got into the low-red (@ ~65-70 mph) but would rise as soon as the speed returned to < 65 mph. I’ve read about possibly checking the oil pressure sender unit with a manual tester, anyone know if a walkthrough for this?

  4. I pumped out the 25 gallons of fuel (in a 22g tank :P), replaced the intank fuel pump, and a new fuel filter, van started right up. Idles beautifully. Problem: Fuel guage flips like a geiger counter. I visually checked the fuel sender unit in the tank as I was replacing the pump and didn’t notice any burn/scorch marks on the portion of the sender unit responsible for the fuel level (little copper? coil thing)

  5. Cruise control does not work at all, at any speed. Fuse is good, haven’t visualized any other portion.

  6. Door electric lock does not work on either driver or passenger side.

  7. Electric Driver window works, but the passenger window does not (both driver and passenger switch elicit no response), fuses appear to be fine, haven’t found the relay switch to test it (need a special tool to remove the door handle so haven’t been able to test the motor)

My main concern is the shifting, everything else is secondary (except perhaps the oil pressure…). I provided the other information because I’m not a mechanic and I know that sometimes several aspects are connected and its nice to have all of the information.

Thanks for your help guys,
-Rob