F30POST
F30POST
2012-2015 BMW 3-Series and 4-Series Forum
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
BMW 3-Series and 4-Series Forum (F30 / F32) | F30POST > Technical Forums > N47 and N57 Turbodiesel Engine / Drivetrain / Exhaust Modifications > 328d coolant temp & thermostat
Post Reply
 
Thread Tools Search this Thread
      01-02-2018, 01:16 PM   #1
Rocklobster
Enlisted Member
United_States
36
Rep
46
Posts

Drives: 2017 M4 ZCP
Join Date: Dec 2013
Location: United States

iTrader: (0)

Garage List
328d coolant temp & thermostat

Within the last 4 months we have experienced a drop in fuel millage with our 328d xdrive. In the past we averaged about 40 in the summer and perhaps 37-38 mpg in the winter here in cold Minnesota.

This fall we saw a mild drop in millage at about 64k miles. Then as it got colder out the milage plumeted further. We are getting an average of 31mpg.

This is my wife's car and we decided to trade for a few weeks so i could diagnose further. The car also seems to have lost performance and finally with colder temps i'm noticing all the signs of a thermstat that is stuck open. Coolant temp is not consistant and gets up to about 180 at best. When below 0deg F it never gets above 175 (read through obdii), and that's only on the freeway. I'm not sure if that's normal but in the past it seemed a consistant 200 deg+ was a common operating temp (per the dash gauge).

The car, being a diesel, always took longer to get to operating temp but would hold once there at around 205. Now it takes forever to get above 150 and when at idle will rarely get above 145. It also drops quickly from 175 to about 145 at stoplights I am taking it in to the dealership for the 2nd time with the issue, they diagnosed "all systems normal" last time we were in for low milage and power. Now with the more prominent coolant temp issue hopefully they will find the problem.

I cant find any info on how the thermostat operates, if it's more than a mechanical thermostatc valve (standard on most cars)? Is it electronically controlled in any way? What is the proper operating temp for the N47?
Appreciate 0
      01-02-2018, 03:18 PM   #2
eugene89us
New Member
United_States
2
Rep
24
Posts

Drives: 2018 BMW 328d
Join Date: Dec 2017
Location: MS

iTrader: (0)

According to N47D20O1 engine information, our engines have conventional thermostat, where coolant temperature is the sole determinant of when the device opens. It is not electronically controlled.

Thermostat starts to open at 88 C (190 F) and is fully open at 100 C (212 F).

Today, we have had a temperature down to 14 F this morning. The needle didn't start to rise until about 3 miles of 45 mph driving. At the light, it dropped again, to then reach its operating temperature after getting on interstate for a few minutes. I didn't feel much change in torque, just lower computer calculated fuel economy and temp gauge staying low until getting on highway.
Appreciate 0
      01-02-2018, 03:24 PM   #3
eugene89us
New Member
United_States
2
Rep
24
Posts

Drives: 2018 BMW 328d
Join Date: Dec 2017
Location: MS

iTrader: (0)

This is after 3 miles of driving at 45 mph with 3 stop signs.
Attached Images
 
Appreciate 0
      01-02-2018, 03:40 PM   #4
catskillclimber
Private
12
Rep
56
Posts

Drives: 328d
Join Date: Apr 2014
Location: claryville, ny

iTrader: (0)

Are you sure your looking at coolant temp and not engine oil temp? We have a 2014 328d xdrive and the only gauge temp on ours is for oil temp. When we get spells where the temp doesn't get above 10F, the oil temp barely gets to the normal reading of 210F after 25 miles of rural highway driving. This is our 3rd winter and it has been consistent.
Appreciate 0
      01-02-2018, 05:00 PM   #5
SSportWagon
New Member
0
Rep
17
Posts

Drives: 2014 F31
Join Date: May 2017
Location: Long Island, NY

iTrader: (0)

Quote:
Originally Posted by catskillclimber View Post
Are you sure your looking at coolant temp and not engine oil temp?
Gauge on far right .. isn't that coolant temp ?
__________________
Alan W
2014 328d SportWagon - Liquid Blue metalic over Black Dakota CPO'd 05/17 with 22K miles
Driver Asst. / Driver Asst+ / Dynamic Handling / Lighting / Premium / Tech / Active Cruise / HK Audio /
Appreciate 0
      01-02-2018, 05:25 PM   #6
catskillclimber
Private
12
Rep
56
Posts

Drives: 328d
Join Date: Apr 2014
Location: claryville, ny

iTrader: (0)

Quote:
Originally Posted by SSportWagon View Post
Gauge on far right .. isn't that coolant temp ?
That is engine oil temp. I seem to recall it is the oil temp at the turbo. If you have an OBDII tool that reads more than codes you can check coolant temp via the OBDII port.
Appreciate 0
      01-03-2018, 06:06 PM   #7
CleanKM
SQUEAKY
CleanKM's Avatar
United_States
45
Rep
176
Posts

Drives: 2014 328d
Join Date: Jun 2010
Location: Washington, DC Metro Area

iTrader: (0)

Quote:
Originally Posted by SSportWagon View Post
Gauge on far right .. isn't that coolant temp ?
Quote:
Originally Posted by catskillclimber View Post
That is engine oil temp. I seem to recall it is the oil temp at the turbo. If you have an OBDII tool that reads more than codes you can check coolant temp via the OBDII port.
I concur, it is the oil temp.
Appreciate 0
      01-04-2018, 10:18 AM   #8
jnecr
Second Lieutenant
86
Rep
244
Posts

Drives: 2014 328d
Join Date: Mar 2017
Location: Raleigh, NC

iTrader: (0)

Quote:
Originally Posted by CleanKM View Post
I concur, it is the oil temp.
Wha?! I had no idea, I also thought that was engine coolant temp. I haven't read the manual, I guess I should...
__________________
2014 328d
Appreciate 0
      01-04-2018, 11:54 AM   #9
catskillclimber
Private
12
Rep
56
Posts

Drives: 328d
Join Date: Apr 2014
Location: claryville, ny

iTrader: (0)

Quote:
Originally Posted by jnecr View Post
Wha?! I had no idea, I also thought that was engine coolant temp. I haven't read the manual, I guess I should...
Actually, the clue is on the gauge. In the lower right is the symbol for oil, an oil fill can. If it was coolant you would see wavy lines simulating choppy water.
Appreciate 0
      01-04-2018, 02:12 PM   #10
Adamr916
Captain
Adamr916's Avatar
United_States
116
Rep
698
Posts

Drives: 2014 328d
Join Date: Sep 2014
Location: Houston, Texas

iTrader: (1)

With my Cummins, it recommends running an grill cover when temps get constantly below 32*. While i never experienced temps that cold while I had my 328d, I'm sure it wouldn't hurt to cover the grills with cardboard and see if it would help any with temps being that cold.
Appreciate 0
      01-05-2018, 04:20 PM   #11
CleanKM
SQUEAKY
CleanKM's Avatar
United_States
45
Rep
176
Posts

Drives: 2014 328d
Join Date: Jun 2010
Location: Washington, DC Metro Area

iTrader: (0)

Its been in the teens here, with single digits later at night for the past week. Mine has been running without any problems and the oil gets up to temp after 40 minutes of running. Glow plug is still strong and she basically starts up almost immediately.
Appreciate 0
      01-05-2018, 06:31 PM   #12
floydarogers
Curmudgeon and Pedant
floydarogers's Avatar
United_States
400
Rep
3,053
Posts

Drives: 2010 335d, 2014 328d
Join Date: Nov 2012
Location: Bellevue, WA

iTrader: (0)

If you search around (I believe in the e90post diesel subforum), you'll note a thread where poster TDIwyse experimented with some cardboard. He's a data nut so was running Torque to monitor temps to make sure nothing bad happened.

I love our diesels electric heater element - one mile/2 minutes and we've got heat from the a/c system.
Appreciate 0
      01-06-2018, 01:40 PM   #13
robbiep
Lieutenant Colonel
United Kingdom
741
Rep
1,733
Posts

Drives: F31 325d M Sport, Z4 20Si
Join Date: Dec 2013
Location: North Wales, UK

iTrader: (0)

Quote:
Originally Posted by eugene89us View Post
This is after 3 miles of driving at 45 mph with 3 stop signs.
That's normal. My 325d (very similar to the 320d/US 328d) takes 4 or 5 miles of driving before the temp needle even starts to move.
Appreciate 0
      01-06-2018, 02:59 PM   #14
floydarogers
Curmudgeon and Pedant
floydarogers's Avatar
United_States
400
Rep
3,053
Posts

Drives: 2010 335d, 2014 328d
Join Date: Nov 2012
Location: Bellevue, WA

iTrader: (0)

Quote:
Originally Posted by floydarogers View Post
If you search around (I believe in the e90post diesel subforum), you'll note a thread where poster TDIwyse experimented with some cardboard. He's a data nut so was running Torque to monitor temps to make sure nothing bad happened..
It's on bimmerfest: http://www.bimmerfest.com/forums/sho...d.php?t=594801
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -4. The time now is 11:03 PM.




f30post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST