Temp. light on, looses antifreeze, temp guage up and down

When it's getting low on those fluids you have to add more. Don't run it low on anything you'll ruin engine. Get it into a shop as soon as possible and have it checked out, to see where the coolent is going. You should be checking your fluid levels when you put gas in the car, especially on an older car. Engines tend to use more oil as the miles get higher on the vehicle. Oil and anti-freeze are cheap engines are not.

Sounds like you might have a blown headgasket.