I have an 02 Civic that keeps over heating. I replaced the radiator and thermostat. It was fine for about a week, then started over heating again. Now my check engine light is on and I think my transmission is going out. Bear with me, I'm a female who does not know anything about cars, but the needle reaches all the way to the 4 on the rpm before it changes gears, and when I'm coming to a stop, it stalls. I'm wondering if the over heating has anything to do with the transmission? Also my fans do work. And nothing is leaking underneath. And i dont think there is anything wrong with the head gaskets because the motor oil is fine. Also, there is no air in the radiator because I made sure there were no bubbles before I capped it. Is there anything else I can have checked for the over heating? Oh and if the transmission oil/fluid is bad, will that make my transmission do what it's doing? Will flushing it out and replacing the filter, or whatever it's called that goes in there that also needs to be replaced, fix the problem? Please help..

 

Park on level ground or facing uphill, wait until the engine is cold, then uncap radiator and check if it is still full to the top. If not, top up with coolant, start engine with the cap off, set the heater dial to full hot, and add more to the radiator as needed to keep it completely full. If you have a lot of bubbles or coolant blowing out of the radiator during this process particularly when you rev the engine, the head gasket is probably bad.