Blown Head Gasket on 100k 2010 128i

[mkhoury6]

Hello 1addicts community,

I am new to this forum, and was hoping to get some advice from this great community about the issues I'm facing with my beloved 2010 128i. Let me preface this by saying that I am by no means an expert on cars; I love cars, I really love my BMW, and I’m learning more and more as time goes on. But know that this post is written by an amateur, hoping to learn more from this community.

I bought this car used with 60k miles, back in 2017. Today, the car has 100k miles. The car has an automatic transmission.

In summary:

A few months ago I began experiencing rough cold startups (bouncing RPMs) lasting ~30 seconds, but then the car would run without any issue. No issues when idling, only on cold startups, every morning. No misfires when accelerating either.

A few months ago I also replaced all spark plugs, ignition coils, as well as the 2 VANOS cylinders & 2 non return valves. I replaced plugs & coils since they were the originals, and due for replacement. And I thought that maybe old/weak plugs/coils could cause this idling issue. It didn’t. Then VANOS change, which was maybe unnecessary, but I hoped it would solve this issue. It didn’t.

Then, over the next few months, cylinder 1 kept throwing misfire codes. I replaced the plug twice, and would swap coils, which would seem to temporarily solve the issue. But then the rough startup would return.

Suddenly the rough startup became noticeably worse. On startup, the whole car would shake, RPMs bouncing dramatically. Oddly enough, no check engine light, no misfire codes. I took the car to the BMW dealer to have it inspected, because I still had an extended warranty on the car.

What the dealer found was that coolant was making its way into cylinder #1. When cylinder #1 was pressurized (~90 psi), the coolant reservoir would overflow. When the coolant reservoir was pressurized (unknown psi) overnight, coolant made its way into cylinder #1. So it would seem the conclusion was: blown head gasket. I never noticed any smoke in my exhaust, but the dealer showed me the pics & videos showing the coolant reservoir overflowing.

I was quite surprised, and skeptical at first. From what I had heard and read, head gasket failure on the N52 was unheard of. Especially for an automatic transmission. I never drove the car that hard, it has just been my daily driver. And for what it’s worth, I’ve always taken great care of it, keeping up with frequent oil changes. I can’t say what the previous owners did though..

So, after this coolant leak was identified, the BMW dealer proposed two options:

1. Valve job, quoted at $14,000!!
2. Engine replacement, quoted at $22,000!!!

Both of those repair jobs are astronomically expensive, and worth more than the entire car! I nearly had a heart attack when they told me that, as you can imagine.

Well, my extended warranty will cover $10,000. (Probably because they know that’s the value of the car and they won’t go above that.) And the dealer has offered a $5,000 discount on the engine replacement job.

So, out of pocket, I’d be looking at $4,000 for a valve job, or $7,000 for a brand new N52 engine.

These numbers still seem so high to me, since I know I could likely find much more reasonable rates at a great indy shop, for either a valve job or used engine swap. But I thought I’d post here and get feedback from you guys.

Any advice or opinion is greatly appreciated.

Thanks,
Mikhail

[BMWCCA1]

Did it ever overheat while you owned it? What will the dealer pay you for it as-is?

[mkhoury6]

Never overheated during my ownership. I haven't discussed selling to the dealer since I was really hoping to repair the car, I love the car and wanted to exhaust all repair options before resorting to parting ways with it.

[SKI-R]

car-part.com for a used N51 (I’m assuming given your California location) and get an Indy to do a full motor swap. Those numbers you’re being quoted are literally insane.

[desertman123]

Don't take your car to the dealership. They gave you those prices to keep you out.

[Papa Popov]

Well this is a bit concerning. I've been having the same rough idle on cold start issue for a while now, and recently started noticing a burning smell on startup as well.

[lvfb]

Originally Posted by mkhoury6

Hello 1addicts community,

I am new to this forum, and was hoping to get some advice from this great community about the issues I'm facing with my beloved 2010 128i. Let me preface this by saying that I am by no means an expert on cars; I love cars, I really love my BMW, and I’m learning more and more as time goes on. But know that this post is written by an amateur, hoping to learn more from this community.

I bought this car used with 60k miles, back in 2017. Today, the car has 100k miles. The car has an automatic transmission.

In summary:

A few months ago I began experiencing rough cold startups (bouncing RPMs) lasting ~30 seconds, but then the car would run without any issue. No issues when idling, only on cold startups, every morning. No misfires when accelerating either.

A few months ago I also replaced all spark plugs, ignition coils, as well as the 2 VANOS cylinders & 2 non return valves. I replaced plugs & coils since they were the originals, and due for replacement. And I thought that maybe old/weak plugs/coils could cause this idling issue. It didn’t. Then VANOS change, which was maybe unnecessary, but I hoped it would solve this issue. It didn’t.

Then, over the next few months, cylinder 1 kept throwing misfire codes. I replaced the plug twice, and would swap coils, which would seem to temporarily solve the issue. But then the rough startup would return.

Suddenly the rough startup became noticeably worse. On startup, the whole car would shake, RPMs bouncing dramatically. Oddly enough, no check engine light, no misfire codes. I took the car to the BMW dealer to have it inspected, because I still had an extended warranty on the car.

What the dealer found was that coolant was making its way into cylinder #1. When cylinder #1 was pressurized (~90 psi), the coolant reservoir would overflow. When the coolant reservoir was pressurized (unknown psi) overnight, coolant made its way into cylinder #1. So it would seem the conclusion was: blown head gasket. I never noticed any smoke in my exhaust, but the dealer showed me the pics & videos showing the coolant reservoir overflowing.

I was quite surprised, and skeptical at first. From what I had heard and read, head gasket failure on the N52 was unheard of. Especially for an automatic transmission. I never drove the car that hard, it has just been my daily driver. And for what it’s worth, I’ve always taken great care of it, keeping up with frequent oil changes. I can’t say what the previous owners did though..

So, after this coolant leak was identified, the BMW dealer proposed two options:

1. Valve job, quoted at $14,000!!
2. Engine replacement, quoted at $22,000!!!

Both of those repair jobs are astronomically expensive, and worth more than the entire car! I nearly had a heart attack when they told me that, as you can imagine.

Well, my extended warranty will cover $10,000. (Probably because they know that’s the value of the car and they won’t go above that.) And the dealer has offered a $5,000 discount on the engine replacement job.

So, out of pocket, I’d be looking at $4,000 for a valve job, or $7,000 for a brand new N52 engine.

These numbers still seem so high to me, since I know I could likely find much more reasonable rates at a great indy shop, for either a valve job or used engine swap. But I thought I’d post here and get feedback from you guys.

Any advice or opinion is greatly appreciated.

Thanks,
Mikhail

it sucks you have the n52 because the n51 has a warranty for that called SULEV that MIGHT have helped. (in my case not so much even tho i am still battling it) my engine locked up on the drive home from long beach to vegas at 93k miles. im not able to offer any insight other than maybe look at the oil filter see if you have any floaties in it

[lvfb]

Originally Posted by Papa Popov

Well this is a bit concerning. I've been having the same rough idle on cold start issue for a while now, and recently started noticing a burning smell on startup as well.

on my 09 128i vert i have oil leaking from the valve cover and right onto the exhaust and burns as well. might wanna check around the cover and see if you have any oil dripping

[Papa Popov]

Originally Posted by lvfb

on my 09 128i vert i have oil leaking from the valve cover and right onto the exhaust and burns as well. might wanna check around the cover and see if you have any oil dripping

That's what I'm hoping it is. I'm due for a VCG but I thought it was odd that it started happening on every startup all of a sudden.

Still need to figure out what's causing the RPM fluctuations on startup though.

[mkhoury6]

For what it's worth, after swapping plugs and coils, my theory for the rough startup was a bad fuel injector that was leaking fuel onto the plug, causing a rough startup. However, the dealer swapped fuel injectors between cylinders and the misfire persisted on cylinder 1. At that point, the next running theory was that the valve stem seals were failing, causing oil to drip into the cylinder, resulting in a rough startup.

So fuel injectors, or valve stem seals, could be possible culprits for a rough startup.

[terced]

Swap in a used n51 at a local independent shop that does BMW. Should not cost you more than $6K

[lvfb]

Ended up parting out the cats, radiator and selling the rest to a guy for 900usd.....

swapped out the fuel pump module, roll over module, seat belt tensioner, entire convertible top, keyfob sensor, long metal bar that goes on the bottom and meets the other long metal bar from the other side of the car (goes from like rear wheel to center point under engine).

spent 5900 on car, got 200 for cats and 150 for radiator

had i changed the fucking oil before trying to take it in for SULEV i would have gotten a new engine....