which temp sender is for the ecm ? the head, or the filler neck ? Thanks

It's the sender with the oval head.

And if you buy one... will need to splice a new Metripak plug to use it.
Years ago GM and others no longer make the old one.

Solder and shrink tube is best for ECM reading this accurately.

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I'm pretty sure the L4 uses the same sensor as the V6 and both the Coolant Temperature Sensor (ECM) and the gauge/light temp sensor are still available. The CTS for the ECM is in the thermostat housing and the gauge/light sensor is in the head. You shouldn't need to cut and splice harnesses. Autoparts stores often sell the CTS sensor as the one for the gauge/light and they tell you the new design requires a new style harness end. This isn't correct.

https://www.autozone.com/en...sor-su109/146258_0_0

Temp Sender is for the gauge
Temp SENSOR is for the ECM
Temp Switch is for the fan

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The V6


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[This message has been edited by fierosound (edited 07-20-2019).]

perfect. thanks