What does the coolant sensor do??? How to test it?

[Aus 0]

On a VR6, '94 - what does the blue coolant sensor do? My engine's dying when coasting to a stop and difficult to start when warm. The blue coolant sensor is often suggested as a possible fix ...

 

- where is it (in really simple language!)

- how to test it to see if it's working

- what does it do?

 

Cheers

[RW1 0]

It's behind the plastic cover on the forward side of the engine just above the rad fan motor in a housing with two other similar shapes sensors. If in the right position, it's the middle one of the three positions and is blue plastic with a 2 pin connection.

 

It senses coolant temp for the engine ECU only.

 

When cold at 10'C about 3,300 to 4,000 ohms

When hot at 90'C about 200 to 275 Ohms.

 

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