[paul e]

Originally Posted by kern417

... there is TSB to replace the turbo if coolant keeps running low with no leaks found

Does ANYONE know where I can find this TSB number before I bring it back in?

[kern417]

Originally Posted by paul e

Does ANYONE know where I can find this TSB number before I bring it back in?

I know I saw it mentioned but I can't find it. The dealer should be able to though. Keep in mind it's not a recall, so they may have to put in the issue description to find the suggested repair. It also may have other specific criteria that your car doesn't meet.

[jparnes1]

Originally Posted by dsc888

I let the engine fun with the cap off to "burp" the system which the heat maxed out at 84 degrees, per the instructions on the BMW coolant container.

Unless your level was so low that the expansion tank was bone dry and air possibly got into the system (unlikely since you didn't get a low coolant warning), there is no need to air purge. FYI, this is how you bleed the cooling system for the B58:
• Open bleeder screw on coolant expansion tank for high
temperature and shut after approx. 10 s, or again till the coolant
escapes.
• Adjust coolant level in coolant expansion tank for high temperature
to maximum .
• Shut the sealing cap on the coolant expansion tank for high
temperature.
• Connect battery charger.
• Close driver's seat belt.
• Switch on ignition by quickly operating the START-STOP button
three times.
• Adjust blower to lowest Level, adjust heating to maximum
temperature.
• Floor the accelerator pedal and hold for 15 s.
• The automatic cooling system bleeding routine is being introduced.
• Start engine.
• Idle speed is automatically increased to 1200 rpm.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• The cooling system bleeding routine has finished approximately
11 min after the engine starts.
• Engine speed drops to idling speed level once again.
• Switch off engine.
• Allow the engine to cool down.
• Adjust filling level in coolant expansion high temperature to
maximum and overfill with 200 ml.
• Close the sealing cap (1) until it lines up with the arrows.

[dsc888]

Thanks, jparnes1! That’s pretty involved. I just followed the instructions on the side of the coolant container. But I’m fine as you alluded to. It was low but not completely empty to the point where I it would be pulling in air.

I will keep an eye on the levels once a month to make sure I’m not truly losing it somewhere else. I checked at 2000 miles and it was low already then. I have a hair over 3,300 miles currently. I’ve not gotten any warnings in iDrive yet.

[Rob340i]

I was asked to report on my car (2018 340i) I have had the car 2 days now. Car has 150miles it was shipped from munich to northern italy where i recieved it, not even an 8 hr drive on a truck. So no real risk of evaporation. The levels were if anything slightly above the max. Car has been sitting in 40* Ferenheit for the last 12 hours. Checked both tanks looks completely topped off! I did notice around the top of the smaller tank around the cap there was some of the fluid there it looked damp. Not sure if this is from sloppy filling or if the system is over filled and leaked slightly.

[BMW11]

Originally Posted by jparnes1

Unless your level was so low that the expansion tank was bone dry and air possibly got into the system (unlikely since you didn't get a low coolant warning), there is no need to air purge. FYI, this is how you bleed the cooling system for the B58:
• Open bleeder screw on coolant expansion tank for high
temperature and shut after approx. 10 s, or again till the coolant
escapes.
• Adjust coolant level in coolant expansion tank for high temperature
to maximum .
• Shut the sealing cap on the coolant expansion tank for high
temperature.
• Connect battery charger.
• Close driver's seat belt.
• Switch on ignition by quickly operating the START-STOP button
three times.
• Adjust blower to lowest Level, adjust heating to maximum
temperature.
• Floor the accelerator pedal and hold for 15 s.
• The automatic cooling system bleeding routine is being introduced.
• Start engine.
• Idle speed is automatically increased to 1200 rpm.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• Idle speed for 30 s.
• Operate accelerator pedal till approx. 3500 1/min , hold engine
speed 10 s .
• The cooling system bleeding routine has finished approximately
11 min after the engine starts.
• Engine speed drops to idling speed level once again.
• Switch off engine.
• Allow the engine to cool down.
• Adjust filling level in coolant expansion high temperature to
maximum and overfill with 200 ml.
• Close the sealing cap (1) until it lines up with the arrows.

wow this is a really involved procedure. I wonder if every BMW mechanic really follows every single step exactly... as when i brought my car in for 1st service they didn't re-set my service and it still was dinging i need service PLUS when i looked at the oil cap to see if they "touched" it and smell if the oil smelled new.. THE OIL CAP WAS LOOSE... being the cap was loose I "ASSUME" they changed the oil and oil filter BUT WHO KNOWS.... oh yeah and my iPhone Charger cord in the glove box was GONE.

[Buzzo]

Never had a low coolant warning, but topped off with about 500ml every 7K miles. At 25K now.

[JRocker3]

Well... 8,000 miles on the odometer and just checked both... they are slightly below the min line... not gonna sweat it for now... I'll top them off within the month.

[wacomlog12]

My 340i Touring had a low coolant warning, topped up the reservoir but took it into the dealer. They're giving the system a pressure test overnight to see if there are any leaks/issues.

[bimmer456]

Originally Posted by RG02GEE

My 340i Touring had a low coolant warning, topped up the reservoir but took it into the dealer. They're giving the system a pressure test overnight to see if there are any leaks/issues.

They did a pressure test on mine and didn't find any issue. Didn't need to keep it overnight though. They just need to pressure test for a few minutes to see that it holds pressure.

[wacomlog12]

Originally Posted by bimmer456

They did a pressure test on mine and didn't find any issue. Didn't need to keep it overnight though. They just need to pressure test for a few minutes to see that it holds pressure.

They didn't get round to looking at it until late in the day hence the sleepover (not an all-night test).
Still a little concerning that it seems it's happening to quite a few B58's and yet they're not sure what the issue is.
Reminds me of the good old E46 days; keep a large bottle of water in the boot

[bimmer456]

Originally Posted by RG02GEE

They didn't get round to looking at it until late in the day hence the sleepover (not an all-night test).
Still a little concerning that it seems it's happening to quite a few B58's and yet they're not sure what the issue is.
Reminds me of the good old E46 days; keep a large bottle of water in the boot

Bmw sells a bag with Velcro to keep a bottle of oil in the trunk for the oil burning cars like the v10 M5. I did have my car being kept overnight once to check if everything was okay after hitting a pothole. Sometimes they don't get to your car till late in the day as there are a million cars they service as everyone gets free maintenance so almost no one diy or goes to an Indy unless the car is past the free maintenance period.

[KGB_123_99]

B48 engine here but I'm also experiencing a very slow coolant loss. Need to top off both tanks every 2-3 months or so. Dealer says "It's under warranty to just bring the car in whenever the light comes on and we'll fill it up".

[bimmer456]

So I checked under my hood just out of curiosity one of the coolant reservoir caps wasn't all the way closed. I think it's the turbo one not sure but the cap doesn't exactly close very tightly. May need to do a recall for better caps. Looks like the no coolant loss group is catching up though so maybe it was fixed on newer cars.

[azuritschwarz]

Originally Posted by bimmer456

So I checked under my hood just out of curiosity one of the coolant reservoir caps wasn't all the way closed. I think it's the turbo one not sure but the cap doesn't exactly close very tightly. May need to do a recall for better caps. Looks like the no coolant loss group is catching up though so maybe it was fixed on newer cars.

the larger reservoir is for the engine, while the smaller tank is for the inter cooler. a few people said their lids were the problem, I would look into it. there's a pretty distinct *click* when the cap is fully closed.

I myself just went in for a slight top up in the big tank, the dealer told me to just keep an eye on things.

[kern417]

I just checked mine again and the threads under the cap are crusty on the engine reservoir.The IC reservoir was spotless. You can also see some of the water spots on top of the reservoir itself that may be from coolant droplets, but I'm not 100% sure.

I cleaned it and will check again in a week or two now that I'm driving the car more often. We'll see if it's leaking past or if it's just residue from when the clumsy tech poured coolant in. I just hit 3000 miles last week.

[Buzzo]

Originally Posted by kern417

I just checked mine again and the threads under the cap are crusty on the engine reservoir.The IC reservoir was spotless. You can also see some of the water spots on top of the reservoir itself that may be from coolant droplets, but I'm not 100% sure.

I cleaned it and will check again in a week or two now that I'm driving the car more often. We'll see if it's leaking past or if it's just residue from when the clumsy tech poured coolant in. I just hit 3000 miles last week.

Same crust on mine, but at 30K. Have been topping off the main reservoir with 200ml every 4,000 miles or so. Brought it up again yesterday at its 30K service:

"Pressure tested coolant system. Found system does not have any leaks and hold pressure. Found cap to leaking and letting small amount of coolant out. Replaced coolant cap and topped off coolant and performed bleeding procedure. Operating as designed at this time."

We shall see ....

[insanecoder]

Been following this issue.. and hopefully its understood and resolved before we are all out of warranty..
It seems to be one of two things at this point:
1) rubber o-ring is allowing coolant leaks (minor) although I wonder if this could account for all that coolant being lost .. cause its alot
2) its being farted out the turbo (major) .. and I suspect this is the real culprit.. that there is a design flaw BMW does know about but isnt public about

wish we could get a tech to release us info about what BMW really knows about this issue

[kern417]

Originally Posted by Buzzo

Same crust on mine, but at 30K. Have been topping off the main reservoir with 200ml every 4,000 miles or so. Brought it up again yesterday at its 30K service:

"Pressure tested coolant system. Found system does not have any leaks and hold pressure. Found cap to leaking and letting small amount of coolant out. Replaced coolant cap and topped off coolant and performed bleeding procedure. Operating as designed at this time."

We shall see ....

If it's just the cap, I'll be happy. I have noticed that sometimes I can smell coolant in the car. It's definitely leaking past something.

[Golo2016]

Any updates on this? I've had to fill it up twice now on my 2016 340. SMH

[insanecoder]

Originally Posted by Golo2016

Any updates on this? I've had to fill it up twice now on my 2016 340. SMH

It looks like an issue for a large % of our cars
Mine sips coolant slowly and levels drop steadily where need to go from min to max fill every 6 months

[Korvo]

The results of this poll are pretty concerning...