2004 honda crv overheats when satting still

Turning on the heater opens up more radiator fluid around your engine and immediately cools it for a while; If it starts heating up again, that is going over midpoint, you need to check it out. Start with a radiator cap.....when was last time u replaced? Your system needs a vacuum, and that is the first place i would replace. It is an inexpensive fix. $5-9 at auto parts store Second look for a leak under ur water pump when u stop or at home? Do u hear any sounds from the front as well....like the bearing makes a high shrill. Where u live is also a key. Are u in Phoenix or up in Canada? Good luck

Well i live in Houston texas and no leaks to the waterpump

replace thermostat , coolant flush , clogged radiator ? I flow check them before replacing them , good idea to test/check things before spending the $$ on parts you don't need

If the coolant temp would not go down after turning on the heater..... that would be the first sign that ur thermostat was stuck closed. But it seems to be working from your comment. Hey it is hot in Houston...OMG..... tough on all cooling systems especially a 16 year old car. Have your local Autozone do a vacuum check for free If u dont have a closed system.....that will also cause a spike over the mid point

How old is your coolant? Or is it just water in there? Who does your radiator service last time?

Well took a better look at it when i start it up one fan on the driver side door runs but the passenger side doesnt is that normal