Fix the antifreeze leak first. Being that it is a 90 car, the hose parts are all probably original (15 year old rubber) Thats a long time. They would be getting soft as they break down. Change them and change the thermostat(180F).
Get someone who knows what they are doing when it comes to putting in antifreeze(if you do hose changes) for it is not simply pour down into the rad neck or overflow and all will be good. Antifreeze has to be poured down the top rad hose into the engine to get fluid behind the thermostat and push out the air pockets.
If not done that way, the thermostat will not open.
Having the hood open does nothing for cooling.
Make sure that all the hose clamps are on tight. Now see where the indicatior needle stops at. That is when the thermostat opens. It will be before the red maybe a 1/4" maybe 1/8.
The fan sensor may be faulty, but you say it does turn on and off. That tells me it is working. Normally they will stick permanently on or off. The sensor is located on the driver's side of the rad with 2 wires. It is normal for it to be irratic. Comes on more often in slow moving city traffic and hot summer days.
The smoke or steam you see coming from under the hood is the coolant fluid steaming off. Fix it. Tighten the hose clamps if nothing else. So long as the needle doesn't go into the red, you are fine.
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Monday, December 11th, 2006 AT 4:23 PM