My 95 Civic Dx coupe is having overheating and cooling fan problems. I have noticed that the cooling fan has not been turning on recently.

These are the things I did:
1. I changed the thermostat, thermoswitch, & radiator cap.
2. I unplug the thermoswitch plug, I used a paper clip to close the circuit at the plug while the car key was at "on", and the cooling fan worked. So, I assume the fan, cooling fan relay & fuses work.
3. When the car is idling, there are pressure at both upper and lower radiator hoses, and both of them are warm/hot. So, I assume the thermostat and radiator cap are fine.
4. I thought the thermoswitch that I just changed was bad, so I bought another one. This is my second new thermoswitch in 2 weeks.
5. I noticed I have heat on when the I turn on the heater.

I noticed the coolant is boiling and leaking from the expansion tank. Cooling fan never on, even though I have been driving the car a while and the temp gauge is above the mid point.

Please help.... Why isn't the cooling fan on????

 

High mileage car?
Sounds like a blown head gasket. Take off your oil cap and see if it's wet with coolant on the backside. If so, it's a busted head gasket.

 

It sounds like the cooling fan is not turning on, and that is causing the motor to overheat...

Did you check the operation of the relay?

Worst case scenario is just wire up the fan to the ignition, so it always stays on when the car is on...

It doesn't sound to me like a headgasket... But I could be wrong... If so, there would be bubbles in the coolant, and some oil residue in the coolant (like an oily film on the surface of the coolant)... Also, some smoke would probably be noticeable out the back...

Here's a quick check, just wire up the fan to the ignition or battery, disconnect the relay, and drive around... If you overheat, then it's not the fan, if you do, then it's most likely head gasket failure...

Good luck!

 

It has 120k miles. Will check the oil cap later.

 

I closed the circuit by using a paper clip at the thermoswitch plug, and the fan worked. So, I think the relay is fine, right?

When I open the radiator cap when the car is cool, I could see white residue in coolants. Is that a sign of blown headgasket, oil getting into the coolant system? There are some white smoke out of tailpipe, but not noticeable.

What would it normally cost to fix the headgasket?

 

All the steps you went through on your first post was everything that I went through when I eventually found out it was indeed the head gasket.

With 120,000 it certainly could be

 

Mind to share where did you take your car to get it fixed? and how much?? Thanks...

 

Sent you a PM