So just recently my HID headlights started to flicker on and off until it just eventually turned off on one side. Switch em off and back on and they work again. So after hooking up a voltmeter, i found out that my voltage drops after my car gets warmer and at normal op temp my bulbs would flicker. Anyone have any experience with this?

 

alternator..... maybe ballast or ignitor?

 

Probably better to post this in the lighting forum.
Are you using a harness with a relay/fuse or direct plug n play into your stock wiring harnesses.

 

Try switching the ballasts around and see what happens...

Jonny