[SimplySpoons]

Hi all!

I have a 2017 X3 xDrive28i, with less than 500 miles on it. I've noticed that after starting it up on a cold morning (around 20° F,) it takes about 10 minutes of highway-speed driving for the oil temperature needle to even move, and from there, it takes about 15 minutes or so for it to reach the second dash within the temperature gauge (which looks to be about 195° F.) Sometimes, it will barely move at all after a 20 minute drive, and after stopping and letting the car sit for a little while, it will start moving after I start the car again.

My first question: what's the operating oil temperature for the F25's?
My second question: Typically how long does it take for your cars' oil temperature gauges to move after starting it on a cold morning?

I don't seem to recall it taking this long when I first got the car. I should note that the car doesn't seem to drive any differently, although it might be shifting a tad bit slower, but that could be due to the cold temperature outside

Thank you!

[Neylus]

I have the same Y/M/Model as you and I have the exact same (curious) warm up observation.

The coldest starts we have experienced are around 45F and the warm-up is far longer than any of our previous/current cars.

I have no idea why this occurs. My first thought was does this engine utilize a thermostat and is it working... I have noticed that the cabin heater blows warm within the first few miles so that's good.

Honestly, I gave up trying to understand the temp gauge as it seems to move up and down a bit mysteriously while driving. It's probably normal for the N20 but definitely new to me.

[Peter_R]

This all depends on the vehicle manufacturer. Some sensors are in the engine block, so you see the actual engine temperature. Others and this may well be for BMW have the sensor closer to the radiator or should I say after the thermostat.

I am only guessing here, but it sounds as though yours/mine is after the thermostat and as it only opens partly and slowly and hence gives you a very low and slow reading.

In the UK mine indicates very quickly and goes to the midway mark of just below 100 degrees Centigrade (212 degrees F). There again I am in southern England, and generally it does not get very cold and so responds relatively quickly compared to the OPs.

[Portimao318]

But oil temp is not the same as water temp, is it not ?
In my wifes Juke I can start driving with a cold engine and after 3 minutes the (digital) needle indicates that the water is warm.

When driving my X3 it takes over 10 minutes for the meter even to move at all, and than it takes 5 more minutes before being on normal working temp (90 - 95 centigrade). In summer it does not take that long.

So I think that water heats up a lot faster than oil , also because it is thicker. Would that be a good assumption ?

[Peter_R]

Originally Posted by Endre2

But oil temp is not the same as water temp, is it not ?
In my wifes Juke I can start driving with a cold engine and after 3 minutes the (digital) needle indicates that the water is warm.

When driving my X3 it takes over 10 minutes for the meter even to move at all, and than it takes 5 more minutes before being on normal working temp (90 - 95 centigrade). In summer it does not take that long.

So I think that water heats up a lot faster than oil , also because it is thicker. Would that be a good assumption ?

Please see my previous post. Engine design pays a very large part and also the positioning of the sensors. The water does heat up quicker because by design most engines have a water jacket around the cylinders, but the fact that oil is thicker as you put it has nothing to do with it.

[Portimao318]

Thanks, Peter.

[Tjalle]

Most cars show coolant temperature - BMW has opted for engine oil, which might be "better" from an engine standpoint, but do confuse people.

Coolant to heater core is picked up at a "hot point" to help out wih heat up of interior.

I.e. you can have (fairly) warm air out of heater outlets, while engine oil is much colder.

It is correct that a leaking coolant thermostat will delay coolant heat-up - coolant is leaking to radiator - but is not to same degree impacting engine oil.

It is prudent to keep revs at low levels at start-up in winter.

All start-up:s are cold start for engine, even in summer. In theory it pays off to use a block heater for up to three hours even at +20 C.

[clivem2]

I was brought up to believe that oil temp is the one to look at. Don't push an engine until the oil is warm - warm oil = warm engine. Makes sense to me. 10 mins or 10 miles is not unusual for oil to become warm.

[F30ed]

I was monitoring coolant/oil temps on both N20 and N55 in current Chicago weather. Oil temp just a few degrees lower than coolant. So if Oil shows 70, than coolant is probably around 75.
Both raise quite fast from start, until interior heater hits in stealing heat from engine to warm the interior. Once it slows down, temp goes up again fast.

[ba ba boosh]

When you start your car, all you need to do is wait until the RPM needle hits about the 1k mark (1-2 mins), then drive off. Steadily, don't push the car over 4k RPM immediately. Your car actually warms up faster when you drive it, opposed to heating it up in parked position.

[Peter_R]

There is a lot of misinformation banded around about warming up cars prior to driving off. The general consensus since I have been driving (since 1960) and this applies more so to the latest technology engines be they Petrol, Diesel or even Air Cooled is that once you have started them you drive off straight away.

The BMW X3 Owner's Handbook states this see page 64...

Originally Posted by BMW X3 Owners Handbook page 64

Do not warm up the engine with the car at a standstill;it is preferable to set off straight away, driving at moderate engine speeds.

[HighlandPete]

Warm up time can be quite varied according to ambient temperature. I note a much slower heat up cycle in my N55 (535i) engine as the temperature drops below freezing. Oil is not up to my 'normal' range of 105 - 110C, (220 - 230F), even after 12 miles driving on open roads at around the freezing point. May only be 90C (195F). At something like -4C (25F) oil temperature needle only starts moving off the stop, (70C/160F), after about 7 - 8 miles.

When we monitor oil temperature, dropping to sub freezing temperatures really shows a slow warm up.

I find the same as F30ed, coolant is just a few degrees ahead of the oil temperature in the N55 engine, during the warm up phase.

Originally Posted by F30ed

I was monitoring coolant/oil temps on both N20 and N55 in current Chicago weather. Oil temp just a few degrees lower than coolant. So if Oil shows 70, than coolant is probably around 75...

As heat management and working parameters are very similar in the N20/26 and N55 engines, we expect similar oil/coolant variations.

I'm also used to diesel engines and oil temperature can be 'miles' behind coolant, in the warm up phase. In sub freezing temperatures oil temperature can drop as engine load is eased off, even after 12 or more miles of driving.

[Portimao318]

Thats why I never go over 2500 RPM the first 15 minutes. I would advise maximum 2000 RPM for Diesel engines.
This is very important if you want your engine to have a long and happy life...

I am sure that many BMW cars get problems at low mileage, because they have not been driven warm properly , and also because they have been pushed up to 6000 RPM way too often (I never do that, unless absolutely necessery while overtaking).

[F30ed]

Originally Posted by HighlandPete

I'm also used to diesel engines and oil temperature can be 'miles' behind coolant, in the warm up phase.

BMW is the first engine where I see oil/coolant temp exchanger as part of design. This explains why oil and coolant a close in temperature. All other engines I had they were separated circuits.

[HighlandPete]

Originally Posted by F30ed

BMW is the first engine where I see oil/coolant temp exchanger as part of design. This explains why oil and coolant a close in temperature. All other engines I had they were separated circuits.

I guess some of it is to get the oil warm more quickly, a key to reducing cold running inefficiencies. But in the process, slows other parts from warming up as fast as we may expect.

I also note our latest BMW petrol engine have more intense under piston cooling from the oil, that also helps balance up the coolant/oil temperatures in the warm up phase.