Temp sensors or temp sending unit/

My question is about a 2000 ford windstar with 3.8 engine. Does this vehicle have a coolant temp sensor and sending unit or just a sensor?

The only thing Rockauto lists that I could see is a temp sensor/sending unit for $10-15. Some cars have a separate coolant temp sensor that reads engine coolant temp for the temperature guage and an engine temp sensor that sends engine temperature information to the computer to determine the correct fuel ratio. Sometimes it takes a service manual to tell the difference and location.

A sensor IS a sending unit. Both terms are used interchangeably for the same item.

You should know, however, that the engine has more than one. It uses one to operate the cooling fan, one to provide “engine demand” readings to the ECU as a variable in the equation it uses to determine the engine’s fuel and timing needs, and maybe even another for the temp gage.

Can you be specific about the problem you’re trying to solve?

From what I see, there’s a coolant temp sensor for the computer and a different one for the dash gauge. There’s also a third one that measures the metal temp of the cylinder head (presumably for use by the computer), but it measures the metal temp only, not the coolant temp.

The sensor for the dash gauge might be referred to as a “sending unit”, but that language usage is mostly just by convention. The “sending unit” term tends to be applied to something that measures a parameter for a dash gauge, and often the sensor is directly connected to the gauge by a wire, rather than the info relayed to the gauge via the computer. But it’s still just a sensor.

Yes I am having heating problem and the gauge will move around. Example: gauge will settle half way but will blow cold air. After awhile the gauge will go down some and I will get heat. Also gas mileage has decreased.

Sorry, George, but where I’m from the terms are completely interchangeable.

Dodge, it sounds like you have air in the system. That’s’ generally a result of a leak. I’d suggest having a pressure test done on the system to start, and using a dye to find the leak if necessary. Once the leak gets fixed and the system purged of air, you’ll have heat when you want it, gas mileage will return to normal, and your gage will settle down and operate normally.

You definitely want to follow up on this. Running the engine this way isn’t good for it, and if the leak is from the water pump you could end up with bigger problems if you don’t address it.


Gotta agree. Thats the way it acts if the fluid level is low or you have a head gasket leak.