last year i had an accident and they changed a few things on my car (radiator, bumper, etc) and i have been having weird issues that have not gone away. i want to get the car checked out, but i'd like to get some info / help first if i can rather than have no idea when i go in.

2006 cobalt se

my coolant level was always 190/192, after the new radiator it stays in the 190's if i am driving, but it quickly rises up to 230 degrees before the fan goes on. after about 210 degrees the car does not perform as well. they said they did not replace the thermostat and a radiator specialist said this is ok. is there some sort of thermometer that can regulate the fan to come on at a lower temperature?

a weird electrical issue is that the digits on the panel are sometimes really low and sometimes really bright. sometimes i can not adjust the brightness. this is on the trip panel as well as cd light and the rest of the stack. but i also noticed the rpms sometimes stop at 0 when the car is turned off and sometimes drop below 0 down to the full down location. probably not much of an issue, but im wondering if this could lead to more problems...

thanks for any help you might be able to provide