i have a crx with b16 i havent driven it for a long time . all of the sudden i started up everything ok but i see that the fan does not kick on after a good 20 min

then i see the temp and the arrow goes up like is getting hot. so what i did is i replaced the fan switch that bolts on the back of the block and the same thing happen i replace the water temp sensor. and same thing. is there any other thing i will have to replace in order to fix this.

i also wire up the fan directly into a switch and it works so there is something that is not letting the the fan work

 

replace the thermostat and bleed the sytem, also you can check with a volt meter to see if your getting power to your fans when you jump the fan switch at the back of the block with a jumper, can be fan relay, had that happen to me once.

 

Stuck T-stat is where I would go from here.

 

did you two even read what the OP posted? Obviously make sure your coolant is full. I do agree with 93formula to check the relay. Otherwise, you have a short somewhere in your wiring. Easy fix would be to hook up a switch and keep an eye on the temp guage. It becomes natural after a little while.

 

I don't have a thermostat but the relay is one of the things I though about I will check tomorrow. Will it matter that I took the t-star out cause I didn't have that problem before even do I didn't have the t-star at that time either

 

Well the fan is one problem, but the Thermostat being absent is a totally different one. A car WILL overheat without a thermostat trust me. Go to your local parts store and get one for a 2000 civic si. Put that in and then troubleshoot the fan