So when you get to uni you are going to want a car. Don't sell it. They don't build them like that anymore. No electronics, no computer, carburettor and rear wheel drive all easy to fix but seldom need fixing.
The only real value in the car is the tyres, battery and registration. The rest of the car is worth very little so it is doubtful it will ever be stolen.

If your friends chuck off at you because of your old car, say "Yeah, but I own it not the bank. I drive cheap cars so I have money to buy cheap real estate. When I own enough cheap real estate I will be able to drive whatever car I like."

Don't sell it.