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Erhan

B47 Temperature drops

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Hi folks I have recently joined to forums. My f10 is fitted with the b47 engine and ever since I had a software upgrade for gearbox harsh changes my temperature gauge seems to taking an age to reach 100 degree mark whether it’s related or not I don’t know how we it started after that or I realised after that. When you monitor temperature through the menu the water temperature will drop sometimes by 10 degrees if you lift of throttle going down the hill. Oil will remain around 95 mark. Two dealers looked at it around August and September time and both said can’t fault the car, however I don’t think this is normal as it didn’t do this before and I bought the car last November and it was not doing it back then. It seems to be worse now it’s winter. Could any b47 owners check theirs to see if it’s only me or others have similar issue? 

 

I would really appriciate anyone’s input on this. 

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some more findings guys i dont know if anyone got the active air vents behind the kidney grill but i think they are supposed to open when more cool air needed and remain closed until the engine warms up however mine are open as soon as engine starts, and close when the engine stopped. Would someone be able to check theirs to see if theirs open up when the engine started please? 

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On 29/12/2018 at 23:15, Erhan said:

some more findings guys i dont know if anyone got the active air vents behind the kidney grill but i think they are supposed to open when more cool air needed and remain closed until the engine warms up however mine are open as soon as engine starts, and close when the engine stopped. Would someone be able to check theirs to see if theirs open up when the engine started please? 

Hi 

 

I checked this over the weekend so outside temp was stated at 6c in the the morning so car was stone cold first start of the morning, the vents opened up immediately.

 

I can only assume they will stay closed below a certain temp freezing perhaps and or possibly i recall reading the B47 engine on the 520d is almost cocooned to retain as much heat as possible so they possibly use the vents to keep the heat in when you stop the car to pop in and out of shops etc 

 

the cold really affects the mpg so every centigrade of temp retained helps i guess 

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14 minutes ago, mudd786 said:

Hi 

 

I checked this over the weekend so outside temp was stated at 6c in the the morning so car was stone cold first start of the morning, the vents opened up immediately.

 

I can only assume they will stay closed below a certain temp freezing perhaps and or possibly i recall reading the B47 engine on the 520d is almost cocooned to retain as much heat as possible so they possibly use the vents to keep the heat in when you stop the car to pop in and out of shops etc 

 

the cold really affects the mpg so every centigrade of temp retained helps i guess 

Ok well, i will see if i can secure a camera in there to see if they will close when the car is in motion, this morning i was late to work so i was driving more eager than my usual in eco mode but oil temperature only manage to crack 90 and that was it. There are no codes stored regarding any temperature wise either, my egr was replaced a year and a bit ago by the looks of it so thats that out the picture. All i have got it either vents are not closing during driving or my thermostat is gone.

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6 minutes ago, IINexusII said:

How far is your work commute?

 

Its 48 miles return so 24 one way. It has hills up and down and some 30 mph areas on route. 

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Myn does take a while to get up to normal running oil temp ie needle vertical, but the heater gets warm within a few minutes i always assumed that if the heater gets warm quickly and you have no loss of coolant all should be fine.

 

i would not place everything on these numbers that you read from the OBD.

 

there will be hi low resistances due to

temperature  causing slight variations in the readings

vibrations can cause electrical connections to be good fair bad causing slight variations in the readings

tolerances of the sensors causing slight variations in the readings

 

so when software is changed again that may interpret the info slightly differently causing slight variations in the readings

 

and if the temp drops when you lift of the throttle  down hill makes sense does it not, as you are not burning fuel there fore not generating more heat from the combustion chamber so the coolant being pumped round will be loosing heat via the rad and the hi air flow passing through it.

 

 

 

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