My recently purchased '89 Si seems to run out of gas while still showing 20 - 25 % in the tank. It will only accept about 10 gallons, though it should hold close to 16. I can't see any damage to the tank exterior, and the fuel pump and plumbing looks OK, too.

Anyone else have similar problems?

 

I found the problem! The fuel pickup tube/screen had come off the fuel pump, so it wasn't drawing from the tank bottom. I added a polyethylene tube (from local hardware store) to the pump, slipped the old screen over it, and reinstalled the assembly in the tank. I was able to start the car with only a few gallons in the tank, which was indicating empty.