95 Accord Ex overheating

[spike7]

When the car is idle it seems to pass 1/2 and the car overheats to0 while driving. I checked the relay and switched another one doesnt help. The weird thing is when I turn off the car the radiator fan turns on and when i turn on the car the fan goes off. I cant seem to figure out what is the problem.

[Palut]

Does it only overheat at idle, then go back down when you start driving? If that's the case, then one of your radiator fans isn't working.

I've currently got a problem on my '95 EX with the condenser fan (drivers side fan) not turning on, so if I idle on a hot day with the A/C on, the temperature gauge will climb over half way. If I start driving, the gauge will drop to normal very quickly.

[AccordCodger]

The weird thing is when I turn off the car the radiator fan turns on and when i turn on the car the fan goes off.

No so weird. When the motor is off, there's no coolant circulation, so the water near the temp sensors heats up enough for the fans to come on. Typically it will cycle a few times and eventually go off altogether.

To test your fans, turn the AC on. Both fans should come on (even if the motor is cold).

[jeffcoslacker]

I might be way off here, because I can't remember if yours has a bleeder for the cooling system near the thermostat, but if it does, try opening it and topping off the coolant from the radiator cap.

Sometimes ones with the temp sensor in the thermostat housing will get air caught there when the coolant is moving, and the sensor's element is dry (can't sense air temp) so the fan won't come on. Then when you shut it down, the coolant movement is no longer forcing the air into that area, and the coolant (now hotter than it should be) will contact the sensor and the fan will run for a period, may be longer than the normal "afterboil" shut-down run.

Sometimes air will even prevent the thermostat from working properly. Ususally when the thermostat is affected, they run normal to slightly hot when idling, then spike way over towards the hot side when you start moving or raise the engine revs off idle.

[spike7]

The car overheats when idling. The car overheats when driving. The fans seems to not go on when the engine is on. The fans go on after the engine is shut down. Even at high temp. the radiator nor the condenser fan goes on. I have already release as much as air bubble I can from the radiator, but it is not working.

[iponnet]

change your temperature sensors and/or radiator fan relay, if u know how test your relay so if it works you dont have to change it...if the fans come on at anytime it means they get juice and they work when told to work,,so the problem is the sensors/relay dont tell it to work on time,,also check your water pump for leakage and/or noise..gl

[AccordCodger]

If his fans come on at all, iponnet, then the relays are OK. They don't control when the fans come on - that's the sensors' job.

[iponnet]

true but sometimes there could be problems inside the relays that get in the way of them working properly ...but most probably its the sensors right

[spike7]

Originally Posted by AccordCodger

If his fans come on at all, iponnet, then the relays are OK. They don't control when the fans come on - that's the sensors' job.

yea it was the thermostat sensor. Now it is fix. Thanks everyone.