Hi guys i need some help with my cooling system.

Car is a 2005 civic si.

currently at idle i have no heat, but when i rev it up i get melt ur face off heat.
Now i changed my thermostat, checked my water valve operation which is good.
I also flushed out my heater core which did seem to help it out, after i flushed it and bleed the cooling system which i thought was good. Now i had heat, but 2 days after again lost the heat.

Also i noticed my fan only comes on when on defrost i know this is normal.When i switch it to vents it seems the fan never comes on. Is that normal. Also if i start the car and just let it idle by itself the temp only gets a quarter way up the gauge. If i work the motor it then will get to half way up the guage. Fan still doesn't turn on though.
Any thoughts on what this could be or any insight is appreciated. Hope someone can help me out. I don't have a tester to test the rad cap just going to replace it tomorrow. Sry for the long story.

 

well just like me on my hatch what i do i just take the thermostate off and conect the fan direct to the ingistion honda such a great car but **** the mess up so much lol

 

lol i don't want to go that route, it doesn't over heat. I'm wondering why when i flush the heater core out i get good heat for a couple of days then its gone again.
Also wondering why the car won't reach operating temp on its own, Car will only go a quarter way up the temp gauge when idling, under normal driving goes half way. Is that normal?
How can u tell if u have a faulty water pump? Other then the weep hole. Any other thoughts greatly appreciated.

 

K i've been doing some searches on this forum and from reading i see there is alot of blown headgaskets being the problem.
Though my vehicle doesn't over heat, actually seems to be maybe a tad bit on the low side of the temp gauge.
I have flushed out heater core which is fine, i've changed thermostat, and watervalve is good. After flushing out the heater core and bleeding system,heat works good, but 2 days later will go back to cold? What would u guys think to blown head gaskets?

 

Get a cooling system pressure tester, and a compression tester, then run checks with both to see what your results are. Are you in prarie winter cold yet?

 

Yes is freaken cold out here . Live in winnipeg manitoba, canada lol.. FREAKEN cold. Thx for all the help guys.