[aliensinner]

Hey guys,

Hope you can help with my little dilemma. Was driving and suddenly got a coolant low stop before engine overheats message. Found out the coolant just drained completely out. Checked up top and there doesn't seem to be any leak closer to the top of reservoir or radiator or any hoses visible from up top. Put in some water to see where the leak is coming from. It's literally like a waterfall draining right out.

Got under and can't see the leak right off the bat since the car has so much plastics and insulation to remove under.

Any ideas which hose or if it's maybe the coolant reservoir tank or the reserve tank the leak is coming from? It's looking more towards the back of the engine. I have attached a picture for reference.

Thanks.

[Orion4]

Since as you said, there is no apparent leakage visible from the top of the engine bay, your going to have to pull the under-panels to locate it. The way it is pouring out, by the pic, you have a fully ruptured hose or, possibly, a hose came off a fitting.

[aliensinner]

Originally Posted by Orion4

Since as you said, there is no apparent leakage visible from the top of the engine bay, your going to have to pull the under-panels to locate it. The way it is pouring out, by the pic, you have a fully ruptured hose or, possibly, a hose came off a fitting.

Thanks.

[430inPR]

Were you able to trace down the leak? I was just driving in traffic and all of a sudden saw some smoke from underneath my 2019 430i. I thought it was some other car but 5 minutes later as I got home I got a high temperature warning on the touchscreen. (Weirdly the temperature gauge never moved from its normal position). Let me know what you found

[TwoBimmer]

Just had the same problem with my 2018 430i. Flatbed to the dealer. I’ll let you ‘now what it is

[TF07Z430i]

I have read a common problem is the small coolant hose that runs from the reservoir to the intake manifold can fail without warning. I guess you have to pull the intake to fix it.

[TwoBimmer]

So my leak was the vent hose from the expansion tank to the cylinder head. Dealer fixed it under warranty in a little over an hour. They told it it is the subject of an upcoming recall and will be replaced again with the new re-designed part. The plastic fails under repeated hot and cool conditions. My dealer is Hendrick Southpoint in Durham NC. They are great.

[Orion4]

Yup! That is relatively common failure. I've gone through 3 in 8.5 years. Granted I'm fairly high mileage at 177,400, so a lot of heat soaking.

[CoopersF15]

Originally Posted by TF07Z430i

I have read a common problem is the small coolant hose that runs from the reservoir to the intake manifold can fail without warning. I guess you have to pull the intake to fix it.

Yup I discovered this around this time last year. Complete PITA but got it fixed just before warranty ran out.

[cfm56d7b]

Originally Posted by TwoBimmer

So my leak was the vent hose from the expansion tank to the cylinder head. Dealer fixed it under warranty in a little over an hour. They told it it is the subject of an upcoming recall and will be replaced again with the new re-designed part. The plastic fails under repeated hot and cool conditions. My dealer is Hendrick Southpoint in Durham NC. They are great.

TwoBimmer, thanks for the details. I wonder if B58 engines are also affected by this issue.

[Jboowan]

Originally Posted by TwoBimmer

So my leak was the vent hose from the expansion tank to the cylinder head. Dealer fixed it under warranty in a little over an hour. They told it it is the subject of an upcoming recall and will be replaced again with the new re-designed part. The plastic fails under repeated hot and cool conditions. My dealer is Hendrick Southpoint in Durham NC. They are great.

Originally Posted by TwoBimmer

So my leak was the vent hose from the expansion tank to the cylinder head. Dealer fixed it under warranty in a little over an hour. They told it it is the subject of an upcoming recall and will be replaced again with the new re-designed part. The plastic fails under repeated hot and cool conditions. My dealer is Hendrick Southpoint in Durham NC. They are great.

Do you have a picture of the hose or the part number? I am experiencing the same problem

[Aziego]

Everything is in this thread.

https://f30.bimmerpost.com/forums/sh....php?t=1889354

Call dealer, more likely than not the repair should be covered as there is a recall on the hose.

[Jboowan]

Originally Posted by Aziego

Everything is in this thread.

https://f30.bimmerpost.com/forums/sh....php?t=1889354

Call dealer, more likely than not the repair should be covered as there is a recall on the hose.

Called the dealer and they said they were looking at the campaign and my car didn't qualify. I took it to a small shop that specializes on German cars. They said my car was leaking coolant from the oil filter housing cooler. So it will cost $1,742 - $100 military discount. I am a mechanic but I will not touch a German car so that shop it is! 🤣

[SaintOnge]

Just got this fixed on my 2019 430i - definitely a known issue at the dealer. All taken care of at no cost under service bulletin B170121

"Replace Cylinder Head Ventilation Line" Part# 17-12-9-845-173

[ST808]

Same coolant issues that turned into engine damage..didn't realize how quickly the the coolant was draining... long story short- I need a new engine.

I have a 2017 430I, first time owning a BMW, converted from Benz owner. Received a recall/factory repair letter a while back indicating a possible problem with collant injection line with this model and year and to come in and BMW will fix for free. I had no indication of low coolant.

Car has just under 48K miles. I had no indication of coolant leak until last week. When light came on, I remembered the letter and scheduled for the repair. Then I bought coolant, refilled the coolant over the weekend. I drove perhaps a total of 20 miles after refilling the coolant. Over the weekend, while running an errand -less than 10 miles car went into limp mode- saying high engine temp, overheating. I pulled over waited and then re-started the engine and went home. Following day drove to the dealership, Same thing happened. Dealership called said they saw the coolant injection line issue fixed it but the overheating caused engine damage and I would need a new engine with a qoute of 21k and they would not cover it as it was out of warranty. I called BMW USA and they denied coverage as well. It is shocking to me the price tag and BMW refusal to cover. The broken coolant line is the cause of my engine damage in my opinion. I am just at a loss as to next steps and thought this community would have some good suggestions. Thanks in advance.

[drcc2]

I'm not anywhere near a dealership. Is the service reimbursed by BMW in some way if it's done at a shop other than a dealership?

[SAH.430GP]

Originally Posted by TF07Z430i

I have read a common problem is the small coolant hose that runs from the reservoir to the intake manifold can fail without warning. I guess you have to pull the intake to fix it.

This is a problem I started out with and only got worse I still have yet to find the problem…. Coolant stoped leaking but now oil leak I have a 17 430GC 80k
I’m about to give up on her tbh

[Charm111]

Originally Posted by ST808

Same coolant issues that turned into engine damage..didn't realize how quickly the the coolant was draining... long story short- I need a new engine.

I have a 2017 430I, first time owning a BMW, converted from Benz owner. Received a recall/factory repair letter a while back indicating a possible problem with collant injection line with this model and year and to come in and BMW will fix for free. I had no indication of low coolant.

Car has just under 48K miles. I had no indication of coolant leak until last week. When light came on, I remembered the letter and scheduled for the repair. Then I bought coolant, refilled the coolant over the weekend. I drove perhaps a total of 20 miles after refilling the coolant. Over the weekend, while running an errand -less than 10 miles car went into limp mode- saying high engine temp, overheating. I pulled over waited and then re-started the engine and went home. Following day drove to the dealership, Same thing happened. Dealership called said they saw the coolant injection line issue fixed it but the overheating caused engine damage and I would need a new engine with a qoute of 21k and they would not cover it as it was out of warranty. I called BMW USA and they denied coverage as well. It is shocking to me the price tag and BMW refusal to cover. The broken coolant line is the cause of my engine damage in my opinion. I am just at a loss as to next steps and thought this community would have some good suggestions. Thanks in advance.

I am experiencing the EXACT problem you've described with my 2017 BMW Convertilble at 94, 571 miles. I just took it to the dealer on 10/24/2023 for coolant leak. They told me it was the Water Pump - I paid $900 to fix. then two months later, red engine overheating lights, I do exactly what you did. Then, ,I take it back to dealer right after Christmas thinking pump failed and they tell me its the oil filter housing and that my engine is probably no good (they are 75% sure) $20K for a rebuilt engine.

But on 10/24/2023, I asked if there were any recalls or known problems. they could've replaced the darn oil filter housing then and I'd still have a great CAR. I'm LIVID. I BELIEVE THIS IS ON THEM, BUT OF COURSE, THEY DENY ANY WRONG!

[KeeKee]

Originally Posted by cfm56d7b

TwoBimmer, thanks for the details. I wonder if B58 engines are also affected by this issue.

I am test driving my sons 2017 430i. It also dumped the coolant. The closes
Place to go was Firestone. They are saying leak in ofh.....really?
Also to replace uptake manifold gasket.$2500 bill!....I had just started my 2 day
Test drive. First day, "oil was low" alert 2nd day " stop car immediately alert"
I am sooo uncomfortable having Firestone work on this engine!
I'd have to tow it 40 miles to a dealer. What to do??

[KeeKee]

So on this cooling system.......we now have a $3400 service bill for multiple issues. Was there ever a recall out there for anything to do with the cooling system on the 430i? I sure would like to get reimbursed for something. We saved the engine by not driving after the warning started.

[quakerroatmeal]

Originally Posted by KeeKee

So on this cooling system.......we now have a $3400 service bill for multiple issues. Was there ever a recall out there for anything to do with the cooling system on the 430i? I sure would like to get reimbursed for something. We saved the engine by not driving after the warning started.

I've tried to get reimbursed from BMWUSA for the coolant expansion hose I paid a shop to fix and was denied.

[KeeKee]

Originally Posted by quakerroatmeal

I've tried to get reimbursed from BMWUSA for the coolant expansion hose I paid a shop to fix and was denied.

Bummer