Question about 1991 Lexus LS 400

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When i start my 1992 sc 400 sumtime the temp go to hight the comes down when i make sharp turn i lose heat when i straten up it comes back dont know what to do

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Think Circulation and Compression and Cooling. Check your antifreeze make sure it is full find the leak if it is losing it (ie. waterpump, heater core, hoses, radiator) feel the heater hoses that go to the heater core and make sure they are both hot so they are circulating. You may have to test the flow in the radiator.I would start by seeing if both main radiator hoses are hot if one is cooler you may have a bad thermostat or plugged radiator. If the hoses are puffing up and you may have an air pocket in the system or combustion in the radiator make sure your head gaskets arent blown. Test and replace your thermostat. replace it if it is not opening with heat on it and closing without heat. If the engine is running rough I would do a compression test and a leak down test. if there is no combustion in the coolant they make a tool that you can measure the tempurature on the radiator it is a laser if the bottom is cold and the top is hot it is plugged. Otherwise you will have to remove the radiator to check the flow at the radiator shop.One thing you need to make sure the cooling fans are working as well if it is getting to temp and never coming on you need to check the fan circuit

Posted on Dec 12, 2010

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Replace thermostat,and flush system,sounds like you low on coolant.


Posted on Dec 12, 2010


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