2017 Elantra 2.0L and the ECT..

[CB900F2]

Hi All

I have a 2017 Hyundai Elantra with the 2.0L , and this engine has a ECT (Electronic Controlled Thermostat) and this is the first car I have owned with such a design coolant temp control system...

I have been pulling some live data off the car (obdii) and I have noticed the coolant temp fluctuates up and down a lot! like a toilet seat!.. I understand that the theory of a ECT is to maximize fuel burn by varying the coolant temp by opening the thermostat based on incoming data, but is this constant drop and rise is normal?

am planning to do a run on the high way with the cruse set and wanna see if I get the same up and down of the coolant temp as I am wondering if the ECU algorithm is will make the same changes to the coolant temp based on constant (flat) data coming into the ECU from its sensors..

My data is from a cold start, and the cars normal operating temp is 100 DegC based on the service manual.

Does anyone else have access to their cars live data for comparison? even if its not a 2017 Elantra 2.0l?.. but it would be ideal if its the same car as mine..

 

[Canadastang]

While I don't have a vehicle with an electronically controlled thermostat, I have watched the Cylinder head temps on both of my cars and it does a very similar thing. IIRC both of my cars have 88*C thermostats and will go from 87/88-95C all day long.

Between the thermostat opening and the fans kicking on and off, there's gonna be some variation.

I wonder how much that thermostat will cost to replace

 

[mk378]

That looks typical of "bang-bang" control where the cooling method is either full on or off rather than proportional. Such as a fan starting and stopping. The amount of temperature variation is a trade-off of not having frequent stopping and starting which increases wear.

 

[JTK]

Originally Posted By: mk378
That looks typical of "bang-bang" control where the cooling method is either full on or off rather than proportional. Such as a fan starting and stopping. The amount of temperature variation is a trade-off of not having frequent stopping and starting which increases wear.


That would be my guess too.

 

[MONKEYMAN]

I don't have much to contribute to your question, but that data is cool.

On Highway I am getting 47 mpg or better with my Elantra so the thermostat must be doing it's job.

 

[CB900F2]

Your getting 47 mpg!.. how the heck are you getting this on the highway?.. I was getting around 6.1L per 100km (38mpg).. But I would drive a bit hard sometimes during this period..

Thanks

Originally Posted By: MONKEYMAN
I don't have much to contribute to your question, but that data is cool.

On Highway I am getting 47 mpg or better with my Elantra so the thermostat must be doing it's job.

 

[CB900F2]

Here is a graph of my 2006 Honda Odyssey.. It does not have a ECT.. Just the old fasion thermostat.. and its very linear , both from cold start to operating temp, and then at operating temp, its pretty linear.. No bang-bang with its control of the coolant temp with cooling with the rad fan and/or the thermostat itself..





Originally Posted By: JTK
Originally Posted By: mk378
That looks typical of "bang-bang" control where the cooling method is either full on or off rather than proportional. Such as a fan starting and stopping. The amount of temperature variation is a trade-off of not having frequent stopping and starting which increases wear.


That would be my guess too.

 

[CB900F2]

bump

 

[SilverFusion2010]

What is the point of an electronic thermostat? Seems like needless complexity to me

 

[CB900F2]

Thats what I am trying to find out...

Originally Posted By: SilverFusion2010
What is the point of an electronic thermostat? Seems like needless complexity to me

 

[Thax]

Originally Posted By: SilverFusion2010
What is the point of an electronic thermostat? Seems like needless complexity to me

The reasoning is to be able to more closely control engine temperature and the fuel/air ratio. The data shown on this graph is completely normal for the 2.0L NU Hyundai/KIA engine. Had to replace this very unit earlier this week, ECT stuck in the open position. Vehicle threw a code P0128. Pretty simple repair 1. drain coolant 2. remove belt 3. remove ac compressor 4. remove ECT, installation in reverse order.