I'm trying to adjust the height of my headlight beams, and there are these white plastic cylinders over what's supposed to be the adjusting bolt that I can't seem to get off. They turn loosely and freely, but I can't pull them off the bolt. Anyone know what I'm supposed to do? Thanks for your time!

What year is the car?

On the older (95-97ish) models the adjusting bolt is the metal shaft that sticks out of the back of that cylinder. It's supposed to have a plastic hex head on the end of it but they always break off. The cylinder things are supposed to be some kind of visual guide for determining the height of the beam but they're always broken too. (Spinning around loosely)

You have to use pliers to turn the bolt when this hex is gone.

 

On some of the newer cars( 2000ish and up) there is a cap type thing over the adjuster that doesn't usually need to be removed. You just stick a Phillips head screwdriver into a slot from above to turn the little wheel with the teeth on it.

Sometimes you do need to pry the cap off to get access to the adjuster.

on mine most of the plastic hex pieces are missing but there is still a hex on the end of the adjuster to move the light. its like a plastic hex over a metal hex on mine.

I have a '95 impreza. I got the adjusters freed up, but where should the level bubble be when they are right??, also there is a line gage on the other adjustment. it has lines to align, but can't find what lines should line up??  THX

 

I have never had any luck with those bubble levels ... I just park level facing a blank wall and put them where I think they should be.  The next time you drive in the fog you will know if you got them correct.