Ok so I have searched and searched and searched some more and still can't find a solution.
So my 99 civic ex cooling fan won't come on but car doesn't over heat. when the vehical is stopped and at idle and only sometimes the heater will blow a bit colder until I accelerate again, and at times when I come to a stop I'll notice the radiator steaming.
I have replaced the radiator, the thermostate, the cooling switch on the thermostate housing, the fan relay and the cooling sending unit/switch by the upper radotor hose and the same problems still remain.
There is no white smoke no stalling issues no starting issues, no leaking of cooling of any kind and I have bleed the system countless times.
Any info would help at this point and sorry if this has been gone over else where deep inside the forums.
Thanks again

 

cooling fan only comes on when your thermostat opens up, this is why the cooling fan switch is located just after the thermostat.
once your car temp goes over 185-190 degrees, the thermostat will open up and your fan will turn on.

to check if your cooling fan works, just jump it with paper clip or wire at the connection.

I cant even get mine to come on because the coolant is doing it's job. I'm waiting till summer to check mine

 

Thanks for the reply. I did all necessary tests, jumping the switch was the first thing I did and fan kicked on, I figured since it's winter it might not be getting hot enough, but you would think after 30 minutes of driving it would reach temp for the fan to kick on no?? Also why would the heater get colder at times and the radiator steam? It's not pushing the pressure out of the cap either seems to be coming out of the bottom possibly bottom radiator hose? Hard to tell with steam lol.

 

It's important that the radiator stay full to the top. A head gasket leak will constantly push air into the top of the engine and the radiator, resulting in poor heater performance and overheating, despite constant attempts to bleed the system. Before the first trip every day when the engine is completely cold, open the radiator cap and confirm it is full to the top.

When the car is moving, especially through cold air, the fan really isn't necessary. The fan is controlled by the temperature of the coolant leaving the radiator. This means that if there is an issue where there is lack of coolant or otherwise an insufficient flow through the radiator, the fan may stay off even though the engine is overheated.

Where is the steam coming out? Any leak anywhere needs to be fixed. You can pressure test the system.

 

Good info thank you that makes sense, starting to seem like it may be a headgasket, but wouldn't there be white smoke? Or is that like a really jacked headgasket?? And it's hard to tell where the steam is coming from, seems like the bottom radiator hose but again it doesn't do it all the time and when it does its cold out so obviously there's aloooooot of steam haha.
I do have to fill the coolant every other day but it's not leaking out any where? Pressure test seems like the next step.

 

You could do a block test or just look for bubbles in the radiator while running the engine (cold) with the cap off. This is the first symptom of a slow leak in the head gasket. Like you said, you won't always see white smoke unless it's "really jacked."

 

Awesome I'll give that a go before I head out for work, the more we chit chat the more I lean towards the head gasket, everything else checks out fine, and the only damn things left to replace are hoses and water pump (which are fine) so yeah ok. Thanks again I'll keep ya updated once I get this sorted out 💪

 

Ended up being a combination of water pump and head gasket, headgasket was the main culprit in the end. Heads torn off and being sent to the machine shop, water pumps off blah blah blah all getting done lol. Thanks again you guys 👍

 

If you have the means, have the deck on the block checked for flatness too. A warped deck can cause your new head gasket to not last very long.

 

 

Everything is working perfect now, no warping, no damage any where, cleaned idle control valve, new head studs....... ARP. uhhh replaced vtec solinoid gasket, another coolant temp sensor and a motor mount while I was at it haha. That connector is super nasty though from when my over flown was pushing coolant out so I'm deffinanlty going to change that as well.