Question about 2003 Lexus IS 300

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Could you please let me know if it is okay to mix

I have a lexus 300 gs, i noticed the engine was overheating today. could you please let me know if it is okay to mix the coolant with tap water.

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It's better if you boil it first. distilled water. They also sell pre-mixed coolant, that's ready to use.

Posted on Oct 08, 2009


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Check that the cooling fan is starting, or that it is not starting when the motor already reaches too high temperature because of a faulty thermic switch.
Test also compression to ensure it is not a ring problem.

I assume you already tested cooland pressure to ensure it is not the water pump, and that you checked your car is not consuming coolant liquid, in that case it is either a leak or the head gasked had not been fit properly.

Feb 27, 2009 | 1995 Lexus GS 300

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