[bimmer456]

I only had low coolant once at 8k miles. Now at 43k miles no issues.

[Swappy]

So I stumbled upon this thread and seeing how my car now has 10k kms, decided to give coolant levels a check.

The bigger tank is below the minimum level while the smaller one was above maximum lol.

This is lame though, had owned so many cars before, never had to deal with coolant loss.

And also I can't get the bigger cap to close properly, is it how it's supposed to be ?[IMG][/IMG]

[Swappy]

Originally Posted by Swappy

So I stumbled upon this thread and seeing how my car now has 10k kms, decided to give coolant levels a check.

The bigger tank is below the minimum level while the smaller one was above maximum lol.

This is lame though, had owned so many cars before, never had to deal with coolant loss.

And also I can't get the bigger cap to close properly, is it how it's supposed to be ?[IMG][/IMG]

Never mind, I just and it is not closed properly .

[N420i]

Any news on this front? Are turbos getting replaced?
I have a B48 and although the loss is slow, I have had to add coolant a few times during the past 9 months. Car is now at 31000 miles and seems to run without a hitch...
Took it to the dealer a couple of months ago while still under warranty and they told me there was nothing wrong with the car, that if the coolant kept vanishing I should bring the car back and they'd top it off for me. Screw that, I don't want it topped off, I want it to stop needing it!!

I purchased a non-oem coolant cap and that didn't fix the problem, if anything it made it worse, which makes me think there's a real possibility the trouble is in the cap seals...

So are we all still just adding coolant when it's low? Has no one found a cause or solution?

I guess as long as head gaskets or turbos aren't blowing I'm not all that concern, but I tend to ask a lot of the engine and track it occasionally and I'm not at all comfortable with it just swallowing coolant and not knowing where it's going...

In my case it's just the coolant in the main circuit though, not the IC one...

[insanecoder]

Originally Posted by N420i

Any news on this front? Are turbos getting replaced?
I have a B48 and although the loss is slow, I have had to add coolant a few times during the past 9 months. Car is now at 31000 miles and seems to run without a hitch...
Took it to the dealer a couple of months ago while still under warranty and they told me there was nothing wrong with the car, that if the coolant kept vanishing I should bring the car back and they'd top it off for me. Screw that, I don't want it topped off, I want it to stop needing it!!

I purchased a non-oem coolant cap and that didn't fix the problem, if anything it made it worse, which makes me think there's a real possibility the trouble is in the cap seals...

So are we all still just adding coolant when it's low? Has no one found a cause or solution?

I guess as long as head gaskets or turbos aren't blowing I'm not all that concern, but I tend to ask a lot of the engine and track it occasionally and I'm not at all comfortable with it just swallowing coolant and not knowing where it's going...

In my case it's just the coolant in the main circuit though, not the IC one...

I hope this doesn't turn out to be a major issue down the pike
..when we're all out of warranty

[dsc888]

Originally Posted by N420i

Any news on this front? Are turbos getting replaced?
I have a B48 and although the loss is slow, I have had to add coolant a few times during the past 9 months. Car is now at 31000 miles and seems to run without a hitch...
Took it to the dealer a couple of months ago while still under warranty and they told me there was nothing wrong with the car, that if the coolant kept vanishing I should bring the car back and they'd top it off for me. Screw that, I don't want it topped off, I want it to stop needing it!!

After reading your post, I went to look at the coolant tanks in my B58 again and they were both low. I posted back in January of this year that I too had low coolant and needed to top off my engine overflow tank by quite a bit, as it was well below the MIN mark. My intercooler tank was at the MIN mark. I topped off both to the MAX make then.

Fast forward to today and my radiator coolant overflow tank was AGAIN below the MIN mark. The intercooler was halfway between the MAX and MIN. I took less to top off the overflow to get it back to the MAX and it took very little to get it to the MAX mark.

This is really odd. I see no evidence of faulty caps with white residue around the tanks. I don’t believe I have head gasket issues either. I believe the factory underfilled both tanks and perhaps they were not “burped” adequately to get rid of air in the plumbing and topped off. But I did top off both tanks and they are both SEALED systems. So where the heck is the coolant going? Could it be the turbos like others have mentioned? Could there be microscopic leaks in the plumping design?

I didn’t mention it the last time I had my oil changed at the dealer but will let them know at my next oil change so at least it’s logged into the system just in case.

[kern417]

Originally Posted by dsc888

After reading your post, I went to look at the coolant tanks in my B58 again and they were both low. I posted back in January of this year that I too had low coolant and needed to top off my engine overflow tank by quite a bit, as it was well below the MIN mark. My intercooler tank was at the MIN mark. I topped off both to the MAX make then.

Fast forward to today and my radiator coolant overflow tank was AGAIN below the MIN mark. The intercooler was halfway between the MAX and MIN. I took less to top off the overflow to get it back to the MAX and it took very little to get it to the MAX mark.

This is really odd. I see no evidence of faulty caps with white residue around the tanks. I don’t believe I have head gasket issues either. I believe the factory underfilled both tanks and perhaps they were not “burped” adequately to get rid of air in the plumbing and topped off. But I did top off both tanks and they are both SEALED systems. So where the heck is the coolant going? Could it be the turbos like others have mentioned? Could there be microscopic leaks in the plumping design?

I didn’t mention it the last time I had my oil changed at the dealer but will let them know at my next oil change so at least it’s logged into the system just in case.

I can't get the dealer to log topping off my coolant. If/when it happens again, I'm simply going to say I have a coolant leak that needs to be investigated so they pressure check the system and bill the labor to BMW. It's nice to have a friendly dealer that tops off fluids for free, but that's not going to fix the issue.

[insanecoder]

Originally Posted by kern417

I can't get the dealer to log topping off my coolant. If/when it happens again, I'm simply going to say I have a coolant leak that needs to be investigated so they pressure check the system and bill the labor to BMW. It's nice to have a friendly dealer that tops off fluids for free, but that's not going to fix the issue.

I too am going to get the dealer to do something about this..
if only to reveal their cards on this
they know alot more than they are telling

[Joopster]

I was just researching this problem when I stumbled on this interesting thread.

Looks like I'm not the only one. In my case, I have a 2012 BMW 335i and I started getting the "low coolant" message several months ago. It comes and goes. The garage where I went to get my winter tires on recently could not detect a coolant problem, it was almost full and they added just a bit extra. Next day, I'm driving and the message pops up again after starting the engine. I know the coolant isn't leaking out.

The people at that garage station suggested the coolant sensor might be dirty or defective.

The engine is not overheating. No black smoke coming from the exhaust.

Looks like I'll probably have to take the car in to BMW for this one.

[hollandog]

Couple months ago I got the low coolant warning. I checked the big reservoir and it was almost completely dry. The small one is fine still above min mark. I topped both back up to the max. This is about 12-18months after my last top off. I thought the issue went away since I didn't notice any coolant loss couple months after my last top off.

The car lease was about to mature so I didn't bother to take it to dealer.

[dragon2181@aol.com]

Has anyone got the TSB or details on turbo replacement? I picked up my 340 about 3 months ago and now it needs coolant every two weeks. I keep a jug in the trunk now.

[bimmer456]

Originally Posted by dragon2181@aol.com

Has anyone got the TSB or details on turbo replacement? I picked up my 340 about 3 months ago and now it needs coolant every two weeks. I keep a jug in the trunk now.

I would bring it in to the dealer you shouldn't have to buy coolant they will top it up for free and check for leaks. Check to see if you are tightening the reservoir caps correctly. Should be covered by warranty.

[bimmer456]

Originally Posted by Joopster

I was just researching this problem when I stumbled on this interesting thread.

Looks like I'm not the only one. In my case, I have a 2012 BMW 335i and I started getting the "low coolant" message several months ago. It comes and goes. The garage where I went to get my winter tires on recently could not detect a coolant problem, it was almost full and they added just a bit extra. Next day, I'm driving and the message pops up again after starting the engine. I know the coolant isn't leaking out.

The people at that garage station suggested the coolant sensor might be dirty or defective.

The engine is not overheating. No black smoke coming from the exhaust.

Looks like I'll probably have to take the car in to BMW for this one.

This is regarding B58 you have N55. Not sure how common it is on that engine. I would take it to an Indy that specializes in BMW.

[filion]

Originally Posted by bimmer456

I would bring it in to the dealer you shouldn't have to buy coolant they will top it up for free and check for leaks. Check to see if you are tightening the reservoir caps correctly. Should be covered by warranty.

At my dealer here in Canada they made me pay for the coolant last time for the topping, but they also did a complete test to make sure that it doesn't leak. He told me it was normal and i shouldn't be worried about the coolant loss...
It's a 2016 with 50k km and i had it top it once.

[dragon2181@aol.com]

Originally Posted by bimmer456

I would bring it in to the dealer you shouldn't have to buy coolant they will top it up for free and check for leaks. Check to see if you are tightening the reservoir caps correctly. Should be covered by warranty.

Originally Posted by bimmer456

I would bring it in to the dealer you shouldn't have to buy coolant they will top it up for free and check for leaks. Check to see if you are tightening the reservoir caps correctly. Should be covered by warranty.

Yes I have been to the dealer twice. Once they filled it and second they did a pressure test with no issues found. The service guys tells me at check out these cars just go through coolant.

Thinking about this for hours last night I realize too that my tailpipe exit is always really dirty even after I recently cleaned it. I

I did find these site that does list the national highway safety TSB summaries for F30. May help others.

http://m.carcomplaints.com/BMW/340/2016/tsbs/

[bimmer456]

Originally Posted by filion

At my dealer here in Canada they made me pay for the coolant last time for the topping, but they also did a complete test to make sure that it doesn't leak. He told me it was normal and i shouldn't be worried about the coolant loss...
It's a 2016 with 50k km and i had it top it once.

I had the issue at 8k miles but hasn't happened since.

[dsc888]

I'd like to make another follow up post to this thread as I once again discoed that my radiator overflow tank to be at the MIN mark after I topped it off on 11/1/2018 based on my last post here. So it took about 3.5 months for me to go from the MAX to the MIN mark. I have not topped it off yet as I was in a rush to go to work but was curious.

The Intercooler Tank was a smidge below MAX so I might need to have that one looked at as well.

So in my situation, it's doesn't appear to be the "Underfilled at the Factory" theory is applying here. It's definitely going somewhere.

As for my history, I have 12k miles on my odometer and it was bone empty in the radiator tank when I first opened it at 1,800 miles back in 11/2017 or about 2 months after I took delivery of my car. I topped off both tanks with BMW coolant and distilled water at 50/50 mix and didn't open the caps until a year later on 11/1/2018 when I come to discover I was low again in the radiator tank and on the MIN mark on the intercooler side. Again it was topped off until today when I took another peek.

I don't see white residue on the caps or around the reservoirs. There doesn't appear to be a puncture at the radiator but might have to look into a rock guard eventually to prevent one from happening due to bad BMW design. So it's possible that the B58 may have issue with head gaskets or turbos. I will absolutely bring it up when I go in for my 2nd oil change in a few months. This is the only fly in the ointment for an otherwise terrific powerplant!

[XutvJet]

Hopefully the heat exchanger in the B58s intake manifold won't start leaking coolant directly into the intake ports like M3/M4 owners are experiencing on some of their cars from leaking heat exchangers. Get enough coolant in the combustion chamber and you could hydrolock the motor or too much coolant in the oil and it will impact viscosity and potentially spin a rod bearing. These liquid to air intercoolers are better in terms of efficiency, but the issues from a leak could be catastrophic.

https://f80.bimmerpost.com/forums/sh....php?t=1570544

[dsc888]

Originally Posted by XutvJet

Hopefully the heat exchanger in the B58s intake manifold won't start leaking coolant directly into the intake ports like M3/M4 owners are experiencing on some of their cars from leaking heat exchangers. Get enough coolant in the combustion chamber and you could hydrolock the motor or too much coolant in the oil and it will impact viscosity and potentially spin a rod bearing. These liquid to air intercoolers are better in terms of efficiency, but the issues from a leak could be catastrophic.

https://f80.bimmerpost.com/forums/sh....php?t=1570544

Thanks for the response and the link. That is truly scary if true on the B58 as there seems to be a pretty consistent pattern amongst owners. I will demand my engine get pressure tested the next time I bring my car in for an oil change.

[XutvJet]

Originally Posted by dsc888

Thanks for the response and the link. That is truly scary if true on the B58 as there seems to be a pretty consistent pattern amongst owners. I will demand my engine get pressure tested the next time I bring my car in for an oil change.

Good plan. At the least, closely monitor the intercooler tank. If it ever starts dropping, take the car in or remove the intake manifold and search for coolant. The chances of hydrolock are probably pretty low, but coolant in the oil of a high performance motor could be really bad and cause the viscosity of the oil to go out spec fairly quickly and cause issues with the bearings, cams, etc. I'd check the coolant tanks at least monthly.

[Soul_Glo]

Bump

[340ix17]

Just picked up my '17 340i last Sunday, pre-owned with ~36k. As of Wednesday morning (had it only 4 days) I was getting the coolant low message and brought it right into the dealership to make sure there were no other lurking issues. I have no idea whether this was the first time, or if this has been a consistent theme with my car, but figured I would add this to the list of cars experiencing the issue.

Service tech stated just before I had showed up there was a separate 340i with the same issue, so clearly this is common to the car. Neither he nor the service manager seemed overly concerned, just told me to keep an eye on it.