[Jules59]

Normally my cars (2009 330D LCI N57) temp is steady at 96C according to my Torque Pro app on my phone.

Today cruising up the motorway with cruise control ON at 2000rpm I noticed on the hills the temp rose to 101C and dropped to 93C on the descents. Giving it some welly it never went above 101C. This widely fluctuating temp is a new issue. The car appears to be running well, has done just over 40Kmiles and managed 43mpg on the 100mile trip.
On reflection Ive noticed a slight increase in temp variability over the last month but as most of my journeys are about 10 miles it didnt jump out at me. Today was a the first long motorway trip Ive done since Xmas.

My feeling this is a thermostat issue. What do others think?

Are there any DIYs on changing the thermostat/s on the N57 engine ? Or is it just like the M57 ?

[Dan-danGT]

That don't seem to bad for a uphill climb. But 96c is not hot at all. 101c is not really hot, I had my 330d Upto 112c on the nurburgring last year and I never got a coolant temp warning.

Just monitor it but I don't see much problem with that also could have been regenerating

[makkan00]

On Petrol, its a different story. I have changed the coolant on my car and replaced it with BMW OEM coolant. Kept an eye on the temp in the hidden menu.

During the summer it was going upto 110C without fan kicking in.
Fan kicks in at about 118C on petrol car (320i). If you drive it in italian style, temp goes up and goes down with cruising. I had 120C max and after searching on internet, I found it was normal for a petrol car.

[Jules59]

thanks. ok i wont worry. I guess its why BMW removed the temp gauge.

Odd how much the temp changes though - I've never noticed such variance on other cars - perhaps the difference between an analogue gauge and a digital readout.

[dj219957]

this is why temperature gauges are damped in cars! to stop people worrying about fluctuating temperatures. bmw chose to remove theirs all together. dont worry about it, its normal.

[Oxygen Thief]

Originally Posted by Jules59

Normally my cars (2009 330D LCI N57) temp is steady at 96C according to my Torque Pro app on my phone.

Today cruising up the motorway with cruise control ON at 2000rpm I noticed on the hills the temp rose to 101C and dropped to 93C on the descents. Giving it some welly it never went above 101C. This widely fluctuating temp is a new issue. The car appears to be running well, has done just over 40Kmiles and managed 43mpg on the 100mile trip.
On reflection Ive noticed a slight increase in temp variability over the last month but as most of my journeys are about 10 miles it didnt jump out at me. Today was a the first long motorway trip Ive done since Xmas.

My feeling this is a thermostat issue. What do others think?

Are there any DIYs on changing the thermostat/s on the N57 engine ? Or is it just like the M57 ?

I'd be more than happy with those temps! I've got the same engine and my temps only get in the region of 88-92C and i'm getting 39mpg average. Looks like its time to get both my thermostats changed if you're hitting those sorts of temps!

Phil

[335DEE]

more than likely DPF regen if getting upwards of 100 . if it drops to below 82 when up to temp , then change BOTH your stats .. they ALL go weak in time and bugger the DPF

[Jules59]

Originally Posted by Oxygen Thief

I'd be more than happy with those temps! I've got the same engine and my temps only get in the region of 88-92C and i'm getting 39mpg average. Looks like its time to get both my thermostats changed if you're hitting those sorts of temps!

Phil

Ive changed the thermostat and guess what, I'm getting a steady 89-91C. No more 93 -103 swings.

[Dan-danGT]

Main stat opening temp is 86c I believe so 88-92c I would think is normal that's all I see in my 330d. You coud have been in a regeneration which is why temp was higher than normal. Also I can manage 43 mpg on a run and my temp is not much different to some others posted

[tmarshall57]

88-92 is completely normal on a 330d