My wife's car has started running warm on and off. At first, I thought it was the thermostat, I replaced that, flushed the engine, radiator and expansion tank and replaced the cap (which was leaking a little). Worked great for about a week, then she started complaining that it heated up at stop signs. I checked out the radiator fans and they work ed fine at the time I checked them, but I'm starting to suspect there's a short in the system and they are working sporatically. The car never overheats, at most it gets up to about 75-80% of the way up and holds there but I want to get this resolved. The problem is, every time I've tried to check it, the problem vanishes. On the 4th, it happened at a stop light, I drove a block and stopped at my mother's house and when I popped the hood, the fans were on and the temp was going down.

Is there some way to check for a short or where should I look? None of the wires look at all worn, at least as far as I've traced them back to the fuse block.

i'm guessingyourcoolant temp sensor is on the fritz. its in the intake manifold.maybe the the thermal fan switch if it has one. they make the fans go on, but not at the right time it seems.

I'm having the same problem with the overheating. Is it filling the expansion tank when you cut It off?

No, although I have found that a small portion of the rim of the expansion tank, right under where the cap screws on, has broken off and on rare occasion, you do get some leakage from the expansion tank. I don't know if that means there's excess pressure in the tank or what, my wife got home one day and said she was losing a lot of fluid from the car, I checked and it was leaking out of the broken section of the expansion tank. I topped it off and it hasn't happened again. I know sooner or later I have to replace the tank, it's an easy operation, I just haven't run into anyone who carries it, or I haven't remembered to ask when I've been out.

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<TD id=HB_Focus_Element vAlign=top width="100%" background="" height=250 UNABLE="off">I got an expansion tank at the dealer for around $65. The problem I had with mine was the radiator was stopped up. They rotted it and flushed the heater core and everything seems to be okay.</TD></TR>
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