My car: 99 civic HB, 1.6l non-vtec, auto, completely stock.

Okay so here it is, a couple weeks ago my temp gauge would rise quickly but only when I was idling. So I did a coolant flush and that seemed to take care of it, even on the hottest day so far (35C) the temp gauge wouldn't even move while sitting in traffic.
Tonight I went for a little drive and it is fairly cool right now and stopped at a drive through to get some food and my temp gauge almost hit the top, turned on the hot air to try and help cool it down but it just blasted cool air. But as soon as I started moving again(had my rpms over 2100) the needle would climb back down, and the heating system got hot again. Could it be my water pump or thermostat thats on its way out, or even something else?

 

Did you hear or notice your fan turn on at all?

 

Yes, there is a slight shudder that I can feel when the fan turns on, I'm half deaf btw... But it only turns on when the car is moving, not when its just sitting there idling.

 

The fan should come on when the vehicle is stopped, theres no point in it turning on whe the car is moving because air is being forced through the radiator from the movement. Do you know where the thermostat housing is? There is a lil electrical connector on it, disconnect it and connect the 2 terminals on the side with the wires running to it with a paperclip or piece of wire and with the car key on II. The fan should kick on, let us know what happens.

 

^^
Just tried it, nothing happened. So I reset and tried it a couple more times, it won't come on. Gunna go check my fuses to make sure that is not causing it. Hopefully its something small and stupid.. I guess that shudder must have been something else.

EDIT: Its not a fuse issue as I hoped it would be. Looks like it may be the fan motor thats gone bad.

I recently picked up a 97 integra for a parts car, would the fan unit swap out from it to the civic without any problems?

 

Could be that or the relay try hooking the fan up directly to the battery, if it doesnt come on it could be a bad motor. But if it does it could be the relay or wiring to the fan motor.

 

How should I go about testing the motor? Just hook a wire up to each prong in the terminal and touch them to the battery? Is there a specific order, + - ? I just don't want to make matters any worse by doing something silly.

 

+- doesnt matter it will just make the fan spin a different direction

 

It worked! So I guess I get to chase down some wires now. Now I know what I gotta do to fix this, thanks alot for your help man. Really appreciate it.

 

No problem! Let me know when you fix the problem, and what it was exactly.

 

Was in fact the relay. Bought a new one then tested the fan with a paperclip, it fired right up.

 

I'm having some what the same issue ... I noticed my car would get warmer then normal and I would loose water.... my radiator was cracked.. I replaced it with an aluminum one, new hoses and new thermostat. My car still goes a I'll above half like once in a great while only when I'm idleing..... water pump and fan are fairly new.... what could be the next issue....

 

Did you bleed the coolant system after changing the radiator? Is the fan(s) coming on? Are both radiator hoses warm after the car warms up?

 

What if the top one is hot as heck and the lower one is cool

 

Did you bleed the air out of the system?

 

Okay, the fan works since I've replaced the relay. But it is still overheating, it won't turn on when its needed. Could it be that the thermostats gone bad? How would I test it?

 

The thermostat is on the motor(top radiator hose leads to it). You can tell by looking at it if its jacked up or STUCK open/closed.