Possible oil temperature software bug

[CarGuy]

Some background. Recently changed my oil using Pennzoil Ultra Platinum synthetic in my 2023 WT. I often travel a 200-mile loop - straight run at 75ish MPH. With the previous oil, Motorcraft synthetic blend, the temp would range from 201-209 (give or take). With Pennzoil, i see an approx. 5 degree drop in oil temp - ranges from 196-201 degrees.

Now for the odd item. When the temp increases past 199 degrees, the gauge jumps to 201 (and 199 when decreasing in tempature). It never lands on 200 degrees. This has been consistent for a couple weeks now. My hypothesis is there is a programming bug. I can hit all other temps in that range accept 200. I’m using the multi-gauge temp screen (boost, oil temp, trans temp, and battery).

Anyone else see this behavior?

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[Fmuguira]

Not trying to hi Jack thread but mind sharing your Pennz Yltra vs MC blend results when you get a chance; besides the apparent temp diff did you see any mpg differences, engine observations, etc. Thx

 

[sportcoupe]

Your OCD is higher than most.

 

[vicorjh]

Some background. Recently changed my oil using Pennzoil Ultra Platinum synthetic in my 2023 WT. I often travel a 200-mile loop - straight run at 75ish MPH. With the previous oil, Motorcraft synthetic blend, the temp would range from 201-209 (give or take). With Pennzoil, i see an approx. 5 degree drop in oil temp - ranges from 196-201 degrees.

Now for the odd item. When the temp increases past 199 degrees, the gauge jumps to 201 (and 199 when decreasing in tempature). It never lands on 200 degrees. This has been consistent for a couple weeks now. My hypothesis is there is a programming bug. I can hit all other temps in that range accept 200. I’m using the multi-gauge temp screen (boost, oil temp, trans temp, and battery).

Anyone else see this behavior?

It may simply be a limitation due to the accuracy specification of the sensor and the resultant algorithmic conversion over to temperature.

This doesn't mean it's out of operational specification, just that the precision might not be all that great.

 

[Coastalcop]

Ok this is a bit technical, but the average sensor has a resistance value of around 60k ohm to call it around 500 ohm. This corresponds to a temp of 20-180 Celsius .

of that 60k range (at a nominal 5.2v input) 20c to 90c “takes up” roughly 55200 ohms of range. The remaining range 90c-180c is in log steps ranging from 300 ohm to 170 ohm.

so In you operating range 194F and up it is actually at its most inaccurate ( small steps to measure as a more minor ohm change results in a greater to lesser temp reported)


it’s like trying to measure 10 feet with a tape measure, pretty easy, pretty accurate. Now measure 1/64 inch with that same tape measure, it much harder to get an accurate reading.

Here’s a quick data sheet of a sensor that is used “generally” in oil/water temp measurement

https://www.reveltronics.com/downloads/datasheet/NTC_TemperatureSensorNpt.pdf

Hope this puts your mind a little more at easy.

your gauge is a approximate

this is from dusting off a couple decades of dust from when I was a metrologist and had to worry about NIST traceability.

 

[da_jokker]

Did they finally certify the ultra for Ford's specs? They're platinum was but their ultra was not last time I looked.

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