[XutvJet]

Originally Posted by 1FUNCAR

Great. Just great. Guess I should have bought another Asian car if I wanted reliability. I thought BMW had their shit together better than this.

My M235 is my first German car (I'm 44) and everything prior was Japanese, except for one mistake of a car, a 1994 Z28 back in the late 1990s. I researched the crap out of the 2 Series before ordering it in December 2015. The good news is much of what's on the 2 series is parts bin shared with the 3 and 4 series and the parts have been around for a long time. I decided to take the plunge and risk into BMW ownership to see if the best BMW on the market at the time was up to the hype. That was over 26 months and 27K miles ago and my M235 has been extremely reliable. It saw the dealer once for a reflash because I got a CEL from Midwest winter gas. That's it. I absolutely love my M235.

If I were to total my M235, I probably wouldn't worry too much about getting a M240, though I'd probably still just get a barely used M2 instead. The coolant loss issue in some B58s is concerning, but BMW has typically made a good effort to repair/recall issues well outside of warranty. The N54 is a great example that. I think BMW is still trying to pin-point this coolant loss issue in some B58s. If it's water that's being lost from the coolant, then we know it's a evaporation issue with the expansion tank caps. If it's loosing coolant too, then it's a much much more serious issue because that means it's being consumed somewhere.

A BMW will NEVER be as reliable as Japanese car, especially once the car is 5+ years old. You should expect to put in $2K/yr in repairs after the 5 year mark. Some years will be better/worse than others. If you're a DIYer like me, you can save mountains of money. Also, since this is the 2 series, it's a bit lower tech thus it should, in theory, have less expensive issues. I wouldn't touch a BMW SUV or anything beyond a 3/4 series with a 10 foot pole. Plus, there's no BMW beyond the M240/M2 that interests me. The company has lost it's way with its other offerings.

[TajoMan]

Originally Posted by XutvJet

If I were to total my M235, I probably wouldn't worry too much about getting a M240, though I'd probably still just get a barely used M2 instead. The coolant loss issue in some B58s is concerning, but BMW has typically made a good effort to repair/recall issues well outside of warranty. The N54 is a great example that. I think BMW is still trying to pin-point this coolant loss issue in some B58s. If it's water that's being lost from the coolant, then we know it's a evaporation issue with the expansion tank caps. If it's loosing coolant too, then it's a much much more serious issue because that means it's being consumed somewhere.

How many confirmed "coolant leak" on B58 have you seen.
I searched briefly and counted less than 5 confirmed.

It's little too early to panic.

Although I do see BMW updated the turbo with new part#, which means they updated something on turbo.

http://www.realoem.com/bmw/enUS/show...diagId=11_6398

Maybe they did find some issue with turbo.
(Too bad mine is Feb, 2017 build)

All the other cooling related parts are still original without update.

[XutvJet]

I've seen very few confirmed leaks, but I've read of numerous owners reporting having to top off the coolant tanks (there are two on the B58) once, and in most cases routinely. I've seen these reports on this forum and the 3/4 series forum.

If I had a B58, I'd check the coolant levels (when the motor is cold) at least monthly. Since the tanks are black, you can't do visual checks without opening them up. The DME will also warn you if the levels get too low, but once you're at that point, you're at risk of introduced air into the system. Not good.

[XutvJet]

Originally Posted by 1FUNCAR

Seems like it might be time for a poll. I read where Wards Automotive named the B58 as their top engine for 2017 so I would hope much of the mystery coolant loss is due to low fills at the factory. But it would be nice to get fresh feedback from B58 owners across all the different series of BMW's. Maybe something for the general board rather than just here on the 2 Series?

Here's an on-going B58 coolant loss poll on the 3/4 series forum.

https://f30.bimmerpost.com/forums/sh....php?t=1324221

[TajoMan]

After I see this poll thread, I'm more toward to 'factory fill issue' than 'coolant leak'.

Majority of ppl are saying that coolant level does not go down after topped up once or twice.

I guess it's BMW's new cost cutting strategy to under fill from factory? lol

[XutvJet]

Originally Posted by TajoMan

After I see this poll thread, I'm more toward to 'factory fill issue' than 'coolant leak'.

Majority of ppl are saying that coolant level does not go down after topped up once or twice.

I guess it's BMW's new cost cutting strategy to under fill from factory? lol

For some, yes, but many are continually adding coolant every 2 to 6 months with some reporting 500ml to 1/2 gallon additions.

[1FUNCAR]

Originally Posted by XutvJet

For some, yes, but many are continually adding coolant every 2 to 6 months with some reporting 500ml to 1/2 gallon additions.

And BMW just shrugs their shoulders? I sent a message to BMW inquiring about known issues with the B58 engine, giving this unexplained coolant loss as an example. They directed me to talk to a trained technician at my dealer. (Haven't done that but will.)

[228]

just got a low coolant warning on my m240i for the first time at 5000 miles

[1FUNCAR]

Originally Posted by 228

just got a low coolant warning on my m240i for the first time at 5000 miles

Have you been checking it regularly or just relying on the sensor?

[XutvJet]

Originally Posted by 1FUNCAR

And BMW just shrugs their shoulders? I sent a message to BMW inquiring about known issues with the B58 engine, giving this unexplained coolant loss as an example. They directed me to talk to a trained technician at my dealer. (Haven't done that but will.)

This how the discussion will go with the tech:

You: Based on research, it appears that the B58 may have coolant loss/consumption issue. Can you elaborate?

Tech: Never heard of the problem with the B58. Anything else you want to talk about because I'm not making any money by talking with you.


That's the sad truth here.

[loudiamond15]

So I first started researching this issue about 2 months ago when I took my 2018 M240i in for its first scheduled service at 9k miles. I started getting the low coolant warning about a week before my appointment. Like most others I read about, I checked both reservoirs and the main one was indeed under the "low" mark. As instructed by the stealership's service department, I topped her off with distilled water until they could get a look at it in a week's time. I did that and did not have the coolant warning come back. I also had no evidence whatsoever of any leaking anywhere I parked. I took it in for the appointment and the tech said the same as most have posted, that it was most likely slight evaporation and wasn't completely topped off from the dealer and there were no leaks of any kind anywhere. I kept a keen eye on it for the next month and saw no issues so I thought nothing more of it.

Fast forward to this past weekend. I took a short trip to a friend's Christmas party who lives about 2 hours away (125 miles one way). I get back into town and right as I'm on my last 5 miles of the trip, the coolant warning comes on again. I get home, park and within minutes I could see a pool forming under the front left (if you're looking at the headlights). I thought it may be water condensation from running the A/C, but nope, it definitely had a blue tint. After the car cooled down enough to check late that night I confirmed that the main reservoir was below the "low" mark again considerably. I called the stealership's service department this morning and scheduled to take it in. It's currently sitting there waiting for assessment.

For reference, I don't drive the car hard a lot. Mostly the only time I really get on it is when I'm merging onto the interstate going to and from work each day. I'd say it's about a 50/50 mix of highway/in-town driving. I just passed 11000 total miles. No mods of any kind, so it's straight factory. I'll update this when I get word back from the service department.

[XutvJet]

If it coming from the front end, probably a rock pierced the radiator or auxiliary radiator. if that's the case, it won't be covered by warranty. BMW has been having issues with radiators getting pierced on the new motors because there's no intercooler to protect it.

[morphomeman]

The problem should be fairly easy to diagnose but if it is indeed an act of god, then you are probably shit out of luck. Hope and pray that it is a loose clamp. In any case, take the car to the selling dealer before you suffer something catastrophic.

[dradernh]

Originally Posted by XutvJet

If it coming from the front end, probably a rock pierced the radiator or auxiliary radiator. if that's the case, it won't be covered by warranty. BMW has been having issues with radiators getting pierced on the new motors because there's no intercooler to protect it.

BMW's solution to this problem is a "rock guard", P#17118485042:


My solution was screens sourced from Lowe's:

[mechatony11]

I apologize for bringing up this old thread. I had a similar issue with my vehicle recently; the radiator coolant was mysteriously getting low. As I further checked the hoses, cracks in the radiator, or head gasket, there was no sign of leakage. It turned out that my radiator cap was damaged and it’s not holding the standard operating pressure anymore, so I immediately replaced it. I came across an in-depth article that may be worth reading. Search for "Mercedes-Benz Check Coolant Level Warning Light on YOUCANIC" and you will see an article that goes over common causes and possible fixes. You can read about it yourself. I hope this information can assist someone else with a similar issue.