Car's running hot...

[Sonics2042]

Hello,

My car has been running hot and I am not sure what to do about it . Ok, here is everything that has happened since it was running normally.

My car was low on oil and my front light was out. The light lense was filled with water (passenger side) so I drilled some holes in it to drain the water. I also replaced the oil with synthetic (was running conventional). After this is done, I started driving down to PR (Pacific Raceways, formally SIR), and I noticed my car was running really hot. I stopped at some gas station and tossed water into the radiator. It helped for a little bit.

When I got home (decided not to race ), I noticed I was really low on radiator fluid. I filled it up all the way and put in some water wetter. It ran really cool for a few days, but now it is running hot again.

Before I replaced the coolant it was redlined at one point and apparently REALLY hot. It's not quite as hot anymore, but the needle stays about 3/4 of the way up after the car is warmed up.

Wierdest thing is that the tempurature on changes like 25 degrees in ~3-4 seconds when I turn on my lights.

Any ideas what the hell my car is doing?!?!

Thanks!
DoranW