Hi,
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I have a problem that is similar but not exactly the same, looking for advice that might help both of us
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My car is a 1991 Mk2
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(SW20) import with a 3SGE engine.
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My car overheats quite randomly, and the problem looks on the face of it like a sticky thermostat, i.e when it does overheat or look like it is going to 99% of the time the guage will suddenly drop back to normal temperature.
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The only things that are confusing me are that the last time it overheated properly
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(didn't drop away like normal) the temp guage was through the roof, yet the heater was blowing ice cold air.
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As I understand it the heater on this engine
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(3SGE) should circulate water independently of the thermostat.
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.
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.
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or should it?? On this occasion I stopped the car, let it cool, refilled the water and carried on.
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This time it behaved and we suddenly got warm air.
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The other thing is the manner in which it overheats.
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If I drive the car like Miss Daisy it behaves fine, but if I give it a little stick, especially if I take it over the power valve at 5k rpm it will almost guaranteed overheat the next time I slow down.
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If it was just a sticky thermostat then surely it would stick regardless of how the car was driven?
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When it first overheated I checked the head gasket by looking for leaks, looking for mayonnaise in the oil and compression tested the cylinders.
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That is all fine.
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The rad cap also holds pressure until it overheats completely then the valve blows off with a nice niose like a boiling kettle
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(takes a little of the sports car
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"cool" away)
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Any ideas would be much appreciated.
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Tar.
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