My car is a 6th gen. civic ex coupe with a B16A from a USDM Si. Last weekend I replaced the timing belt because the motor has about 85K on. I also replaced the water pump for kicks. I noticed when i'm driving at night all the lights; heads, tails, deck, dash, gauges, etc. all dim and then return to normal brightness. This is on a seemingly sporadic interval, sometimes quick dims/brightens and other times it stayes dimmer for a long period then after some driving does it again. I should note that it is not a huge difference but enough to be very annoying. It doesn't matter whether i'm idling or in the red. Although when i'm idling and it dims the RPM's do seem to drop slightly (<200). It doesn't do it when the engine is off. Any advice would be greatly appriciated! Thanks everyone.