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Easy computer coolant temp sensor test

Old 10-03-2018, 12:19 PM
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Join Date: Jul 2018
Location: Miami Florida
Posts: 26
Default Easy computer coolant temp sensor test

Before you waste money replacing the collant temp sensor, you can test the system like this.
With a cold start, the engine should idle around 1500-1700 RPM
The temperature gauge will show nothing.
After a while, the RPM will drop to 1200 + - 100 RPM.
At about 1100 or so RPM, the gauge should be moving up but still on C (some may differ a little on the up side).
At 1000 RPM, the gauge should be a few notches up.
From that point on, the RPM will decrease in exact correlation to the temperature increase.
As the RPM goes down the temp gauge goes up until it is showing about 1/3 or 1/2 and the RPM is about 700+ - RPM.
If your car passes this test, any problems you have are not likely to be the coolant temp sensor/switch.
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