[MN435]

So I noticed after driving my 2014 435i for about an hour or so my temperature gauge started going down...!? I live in California so there's no way it's because of the weather. This was a pic I took after said one hour drive when I started noticing my temp gauge going down:

I felt like I heard some low vibrating noise at one point whenever I was stopped at alight, but it might or might not have been my mind making things up. After all, at this point I was already kind of sketched out about why in the hell would my temperature start going down. I LITERALLY saw my temp gauge go down tick by tick as I was driving. Then I stopped at my destination and drove again in like 30 minutes. Everything seemed fine.. Engine check ran fine, no dash warning signals and the temp gauge was going up again.

Wondering if anybody ever had anything like this ever happen to them?? I'm going to bring it into the dealer regardless, but just wanted some input.

Sent from my iPhone using Tapatalk

 

[shaik786]

While you are driving, RPM's are relatively high compared to a standstill when the aux fan kicks in and the engine temperature begins to fall, rather quickly. And then when the car is at a standstill (lower/minimum RPM), the fan stops blowing (considering the engine temp is not high) and the temperature starts climbing until the temperature is high enough for the fan to kick in. This is normal unless the temperatures are reaching too high or too low at any point in time.

 

[need4speed]

while you are driving, rpm's are relatively high compared to a standstill when the aux fan kicks in and the engine temperature begins to fall, rather quickly. And then when the car is at a standstill (lower/minimum rpm), the fan stops blowing (considering the engine temp is not high) and the temperature starts climbing until the temperature is high enough for the fan to kick in. This is normal unless the temperatures are reaching too high or too low at any point in time.

+1

 

[mossman35]

Also keep in mind that BMW has designed the cooling system to anticipate cooling before it's needed. For example, if you hit the throttle hard it will immediately increase cooling before the engine temperature actually increases. In the E90 there was actually a heater in the thermostat that would artificially raise the temperature for this purpose. I am not sure how it is done on the F30 but I am sure they would have kept the anticipatory nature. It's imperative that the engine remains within operating temperature given the tight tolerances and large use of aluminum.

 

[jygesq]

you should guage is buffered to stay in center

something is wrong if it goes down, maybe thermostat is staying open. Let dealer fix it

 

[chiefneil]

http://www.bimmerfest.com/forums/showthread.php?t=865745&highlight=n55+engine+manual

See post #15

 

[tturedraider]

I'm not sure why the OIL TEMP is dropping, but the gauge does not measure coolant temperature. It measures oil temperature. Oil temperature changes differently than coolant temperature.

 

[mr shickadance]

oil temps flucuate depending on a lot of different factors, dead stop traffic, high revving, easy driving, all things are going to cause swings in oil temp, it's not as flat as coolant temp.