It surprised me.

Now, this isn't exact, as it idled for five minutes, since I started the engine when we arrived at the vehicle with the luggage cart to load it, but the coolant reach steady state after about 20 minutes (including the initial five minute idle). Of course, it was not a straight line, and most of the temperature increase took place early at a higher rate of change, so I'll give a few data points to give you an idea of the warm-up curve.

Initial conditions (according to X5 OBD-II data)

10.4 degrees F ambient, 12.2 degrees F coolant.

02 minutes 10 and 43

03 minutes 10 and 54

05 minutes 12 and 68

Then started the drive to the interstate...

08 minutes 14 and 113

Entered the Interstate at about 9 minutes and drove at 50 MPH initially...

09 minutes 16 and 123

10 minutes 10 and 147

12 minutes 08 and 160

15 minutes 08 and 167

20 minutes 08 and 176

23 minutes 08 and 183

29 minutes 08 and 185

Then it stabilized at 185 and stayed there for the next hour while I cruised at about 70 mph until I stopped at a rest area.

I forgot about the initial idling on that stop while I loaded the vehicle, so I'll check the data and see if I can find one more representative of a normal start without the long idle at the start, and post it. Maybe I can even figure out how to export the graph with the curve, as it give a clearer picture.

So, roughly speaking, I'd say it would normally take 10-15 minutes from a cold start at 10 degrees to get to 90-95% of operating temperature.

My plan to to collect enough data that I get a good idea of how long it takes to warm-up at various temperatures so I can make an estimate, since we have no temperature gauge any more, e.g., from zero, 32, and 70.

I'll bet the new redesigned X3 coming up won't... at least not in the U.S.

Yeah, I don't know what a 4.8 would show.


You can buy the CarChip for about $100 to $150. You just plug it into the OBD-II port and then later download the data to your computer. It hold about 40 hours of data I believe, depending upon the sampling interval you choose for the parameters. Most the the data capture works with BMWs, but many of the parameters do not apply to diesels and are not logged, e.g., O2 sensor data, It will also log OBD-II error codes which can be read when downloaded to the computer.

I have an older version, but here's a link to the latest:

CarChip® Pro by Davis

Thanks. That looks very interesting.

Just wish there was a firmware update to the idrive that would get temp on screen.

Yeah. If BMW was smart, they would follow Ford's lead with their hybrid. Ford has an LCD instrument cluster and you can choose three levels of information you wish to see. That seems the best solution:

Video: The 2010 Ford Fusion Hybrid’s instrument cluster

New High-Tech Ford Hybrid Instrument Cluster 'Rewards' You for Efficient Driving : TreeHugger

BMW could easily add one more selection to the idrive. This selection would turn the idrive screen into a secondary instrument cluster and could show graphic pseudo-gauges of engine coolant temperature, instantaneous MPG, and/or other informational items that some enthusiasts want to see. Someone earlier mentioned airplane instrumentation. This is a similar approach to the airplane instrumentation which draws pseudo-gauges and allows the pilot to bring them to the screen, and which also automatically displays the appropriate gauge when an abnormal operating condition is detected. It wouldn't require any hard point or physical dash changes, since it would be a software implementation using data the engine computer already has available. They could even make it an extra cost option and make some money on it!

I thought the rev counter shows a variable 'limit' that increases as the engine warms up. Won't be everybody's deeal solution but it does provide some guidance.

Peter T

Now that's cool. I would love to customize the look of my display.

Hmmm, I can't say that I've noticed that. I'll have to look again.

I would be quite happy with that, but it is not on my X5 Diesel, although the gauge appears to have been styled for it at one point (to match the appearance of the speedometer which uses a similar approach to show the cruise control speed with a white segment on a rotating ring/disc which shows through a cutout). I believe it is only the M vehicles that have this "limit" feature.