Trying to use a prismatic constraint as inverse kinematics constraint

[Festivereinhard2 (Festivereinhard)]

I have this robot which has arms that i want to be able to move with inverse kinematics. The arms have been rigged correctly, but theyre on a part that I only want to be able to move up and down.

So to do this, i set a prismatic constraint to two attachments which are on the c0 and c1 cframes of the motor6d. What i expected to happen was that that part could only move up and down when moved with inverse kinematics. But when I tested it it couldnt move up and down, and just freely rotated in any direction. Its as if its ignoring the prismatic constraint.

I checked to see if the attachments had the right CFrames:
Motor6d:
c0 pos: -1.3, 1.65, 0
c0 rot: 0, 0, 90
c1 pos: 0,0,0
c1 rot: 0, 0, 90

Attachment 0:
pos: -1.3, 1.65, 0
rot: 0,0,90

Attachment 1:
pos: 0,0,0
rot: 0, 0, 90

Does anyone know what is going on? are prismatic constraints just not supported for inverse kinematics?

[Festivereinhard2 (Festivereinhard)]

After some testing i have come to the conclusion that IKcontrol does not support prismaticConstraints. When I tried animating the robot and turned on IK, it worked fine.