What's the importance of the sensor on the water neck coming off of the head on the front (radiator side) of the engine? I know JDM motors don't have it... and usdm motors have it... hence why you have to switch the neck with the pre-drilled and tapped hole from your old motor...

Would the absence of this sensor using a USDM ECU cause a CEL or any adverse effects?

 

ttt

-PHiZ

 

nope its just a fan switch, usdms have two, jdm only have one, it wont throw a CEL though in any case.

i suspect it is a weight saving mod in JDM land,