my engine temp gauge on dash always stays in the cold position, do I need to replace the engine coolant temp sensor and if so where is it located 4.0 ltr engine

 

you will find one at Autozone or O'Riley's, then you will see it on the top/front of your engine... it is brass

 

This thread:
https://www.clublexus.com/forums/ls-...ange-pics.html

 

I just did a quick look at the above tutorial and that is for the engine coolant sensor. The gauge sensor is a ONE wire sensor that is much smaller and in the same are where that engine sensor is. The engine sensor has multiple wires connecting to it, and is for the EFI system. The gauge system is separate.

 

If you change the sensor and that doesn't fix it then it's most likely the cluster, I replaced mine for the needle lighting and the new one also fixed the temperature gauge.

 

Anyone with an original.thermostat should replace it.. (OEM only) ..20+ year old rubber seal in thermostat interior can break or separate causing the thermostat to not fully close preventing warm-up or it ends up lodged/clogging an engine coolant passage.. = $$$
It will.quickly pay for itself

 

My head must be elsewhere...geeze

 

If the needle never moves I would be looking at wiring and the cluster first. Give the top of the dash a good slap with your palm once the car is warmed up. Sounds crazy, but the speedo in these cars like to stick and every time I've seen it happen a slap on the dash popped it off of zero. It would also be good to shoot your thermostat housing with an IR gun when it's at operating temp to make sure your thermostat is not totally wide open.