My coolant temp 335D

AWBimmer · 03-30-2013, 05:40 AM

Did the engine coolant temp gauge check yesterday and on startup it was 16 degrees

so I got worried and decided to take it for a spin. I saw the temp rise as I Was driving so I felt reassured and then it stayed static at and about 80-82 degrees mark. I know had I continued driving at national speed limit, it would most likely have gone up but just double checking with you folks that that's in the right region?

I've also noticed that my Avg MPG has dropped from 37ish to 32.8 over the last few months. Maybe the cold weather isn't helping but my route hasn't changed at all and neither has my driving style. 40 mins to work (20 miles), 15 of those miles are 30-50 zone and 5 remaining miles are 60-70 mph zone.

I do know the red boost pipe has black oil / residue on it but the drip tray seems okay. I called up Chris Plummer, a very known local Indy here who said if its not causing me any problems, don't try fixing it. He said unless I notice lag in boost or dramatic drop in mpg then I shouldn't go looking for fixes - I suppose he is right.

I guess my aim is/was prevention not cure, at this stage, can anyone advise why my mpg has dropped and whether I should be worried about the boost pipe?

Cheers,
Sam

Ps I'm not that fussed over few miles per gallon here and there, but when I know the car is capable of 4-5mpg more, then it bugs me.

ssc330d · 03-30-2013, 07:31 AM

Quote:

Originally Posted by AWBimmer

I saw the temp rise as I Was driving so I felt reassured and then it stayed static at and about 80-82 degrees mark. I know had I continued driving at national speed limit, it would most likely have gone up but just double checking with you folks that that's in the right region?

I wouldn't be too confident that it would rise any higher than 82. Before I changed my thermostats, mine sat at those temps - and didn't rise any higher no matter how I drove it. I was never aware of a regen taking place.

After the stat change it rises to 92 degrees and I have been aware of 3 regens (1 even started driving around town).

As far as mpg goes, I never checked mine before the stat change, but earlier this month I drove from Co. Durham to Stansted and back. A combination of quiet night driving on cruise control and on the way back normal daytime (non cruise control). I couldn't believe it - the car averaged 49.6mpg!!

e92liv · 03-30-2013, 09:09 AM

I had the low coolant light come up earlier this week and short journey the next day before topping the coolant up I noticed the fan was on and the vents open- never really notice the fan running before

Anyway I topped her up with coolant and googled the secret menu to show my coolant temp - tends to run between 80-95 but I've seen upto 105 when driving quickly? This is with outside temp around 5c and aircon set to auto 19c. Is this normal?

Oh and mine Is a 320d 177bhp with efficient dynamics

philmots · 03-30-2013, 01:32 PM

OP - Have you changed your thermostats already yet?

If not I'd say they need doing.

Mine has improved so much since doing them and regenerations have happened. I did mine around the same time as the guy above and I too have noticed 3 regenerations, and again one happened while round town.

These ones last a lot less time than the first one did and they don't smell half as bad.

AWBimmer · 03-30-2013, 02:06 PM

I haven't changed the thermostats ... where do I get them from and are they DIY or best done through someone experienced? What are the rough costs associated with this and what exactly will changing these do to the car?

I need some reading material Lol.

philmots · 03-30-2013, 02:09 PM

I normally hate it when people say 'use the search button!' but...

If you have a look through some of my past posts (last month or two) I've written a lot about changing these 'stats. There's a lot of good info.

Ultimately, if it doesn't reach temps then your DPF won't regenerate.

AWBimmer · 03-30-2013, 02:33 PM

Guilty as charged! I'm usually good with search button but I didn't on this occasion lol. Cheers mate.

daveleach · 03-30-2013, 02:37 PM

Is there a test to do the thermostats when there removed to see if there opening/closing correctly?
Or is it a case of once there out might as well change them?

philmots · 03-31-2013, 08:28 AM

You're best checking your temps. If they're not 88-92 one or both are broke. You may as well do both.

You can tell with the EGR one easily though. Blow through it, if you can it's stuck open.

03-30-2013, 05:40 AM	#1
AWBimmer Major General 344 Rep 6,176 Posts Drives: E92 335D Pre-LCI \| E63 M6 V10 Join Date: May 2011 Location: UK iTrader: (4)	My coolant temp 335D Did the engine coolant temp gauge check yesterday and on startup it was 16 degrees so I got worried and decided to take it for a spin. I saw the temp rise as I Was driving so I felt reassured and then it stayed static at and about 80-82 degrees mark. I know had I continued driving at national speed limit, it would most likely have gone up but just double checking with you folks that that's in the right region? I've also noticed that my Avg MPG has dropped from 37ish to 32.8 over the last few months. Maybe the cold weather isn't helping but my route hasn't changed at all and neither has my driving style. 40 mins to work (20 miles), 15 of those miles are 30-50 zone and 5 remaining miles are 60-70 mph zone. I do know the red boost pipe has black oil / residue on it but the drip tray seems okay. I called up Chris Plummer, a very known local Indy here who said if its not causing me any problems, don't try fixing it. He said unless I notice lag in boost or dramatic drop in mpg then I shouldn't go looking for fixes - I suppose he is right. I guess my aim is/was prevention not cure, at this stage, can anyone advise why my mpg has dropped and whether I should be worried about the boost pipe? Cheers, Sam Ps I'm not that fussed over few miles per gallon here and there, but when I know the car is capable of 4-5mpg more, then it bugs me. __________________ BMW E92 335D \| Lower Klasse IG: @that.m6
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03-30-2013, 09:09 AM	#3
e92liv Second Lieutenant 44 Rep 275 Posts Drives: F10 Join Date: Feb 2011 Location: North West, UK iTrader: (0)	I had the low coolant light come up earlier this week and short journey the next day before topping the coolant up I noticed the fan was on and the vents open- never really notice the fan running before Anyway I topped her up with coolant and googled the secret menu to show my coolant temp - tends to run between 80-95 but I've seen upto 105 when driving quickly? This is with outside temp around 5c and aircon set to auto 19c. Is this normal? Oh and mine Is a 320d 177bhp with efficient dynamics
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03-30-2013, 01:32 PM	#4
philmots Lieutenant 103 Rep 511 Posts Drives: M340i Touring LCI Join Date: Sep 2005 Location: Yorkshire iTrader: (0)	OP - Have you changed your thermostats already yet? If not I'd say they need doing. Mine has improved so much since doing them and regenerations have happened. I did mine around the same time as the guy above and I too have noticed 3 regenerations, and again one happened while round town. These ones last a lot less time than the first one did and they don't smell half as bad.
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03-30-2013, 02:06 PM	#5
AWBimmer Major General 344 Rep 6,176 Posts Drives: E92 335D Pre-LCI \| E63 M6 V10 Join Date: May 2011 Location: UK iTrader: (4)	I haven't changed the thermostats ... where do I get them from and are they DIY or best done through someone experienced? What are the rough costs associated with this and what exactly will changing these do to the car? I need some reading material Lol. __________________ BMW E92 335D \| Lower Klasse IG: @that.m6
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03-30-2013, 02:09 PM	#6
philmots Lieutenant 103 Rep 511 Posts Drives: M340i Touring LCI Join Date: Sep 2005 Location: Yorkshire iTrader: (0)	I normally hate it when people say 'use the search button!' but... If you have a look through some of my past posts (last month or two) I've written a lot about changing these 'stats. There's a lot of good info. Ultimately, if it doesn't reach temps then your DPF won't regenerate.
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03-30-2013, 02:33 PM	#7
AWBimmer Major General 344 Rep 6,176 Posts Drives: E92 335D Pre-LCI \| E63 M6 V10 Join Date: May 2011 Location: UK iTrader: (4)	Guilty as charged! I'm usually good with search button but I didn't on this occasion lol. Cheers mate.
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03-30-2013, 02:37 PM	#8
daveleach First Lieutenant 26 Rep 306 Posts Drives: 335d Join Date: Feb 2010 Location: berks iTrader: (0)	Is there a test to do the thermostats when there removed to see if there opening/closing correctly? Or is it a case of once there out might as well change them?
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03-31-2013, 08:28 AM	#9
philmots Lieutenant 103 Rep 511 Posts Drives: M340i Touring LCI Join Date: Sep 2005 Location: Yorkshire iTrader: (0)	You're best checking your temps. If they're not 88-92 one or both are broke. You may as well do both. You can tell with the EGR one easily though. Blow through it, if you can it's stuck open.
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