Pontiac Firebird Forum : “my headlights on my 1988 firebird wont go down but the motors work How do I fix ...”

Check to make sure the joints or elbows are greased and that the wires are still attached correctly to the servo motors.  Usually that is a typical problem. Could be warping of the mechanical joints.  Check thoroughly.

Yea i have the same problem, but sometimes one goes up and the other dosn't or one goes down and the other one dosn't

It sounds like your ecu or one of your relays is not correctly in interpreting the electrical signals going out to your wires and out to your servo motors.  I would suggest a shop to look at it.  Usually electrical wires components can be dangerous without a proper manual or guide.