[agustincuenca]

Hi there!
I never though I would end up writing this.
I recently bought a 2008 335i with 75k miles that I checked from up to bottom and inside out, ALL signs were good, no extreme interior wear, paint looked ok for the age, all electronics good and most important, engine looked solid, no overheating, clean, no rare sounds or noises, etc, clean carfax history, test drive and was all good.
The dealer gave me 30 days or 1,000 miles warranty which is 4 days away from expire and last Friday after a short trip to the airport I notice a strange rattle from the engine when revving the car between 2.5-3k rpms and also at the end of the range, over 5.8k rpms.
I took it to another BMW dealer that I have been working with in the past to a diagnose just before the warranty ends and after the weekend he came back to me stating that the problem is on the lower end of the engine, most likely the rod or bearings that leads him to believe the car was overheated or run with low oil at some point and recommends changing the entire engine!
Bad news! so, I would take the car to the dealer I bought it from but, what would you suggest? get my money back (if that's even possible) or make them fix the car? I've checked some rod knock engine videos and the sound is nothing like it. My rattle is more like a lose piece of tin vibrating while revving but only present at such given rpm ranges.
I really don't know what to do, I'm lost and have no aftermarket warranty whatsoever. Although I have money to spend I don't like to do it.

I will try to post a video tomorrow once I get the car back.

Any opinion/suggestion/experience counts.

on a side note, I did lots of searches here and youtube and found nothing similar to what's happening to my car.


thanks!!!

[YouAreMyWorld]

From your description it sounds more like waste gate rattle, meaning the replacement of turbo's would fix said issue.

I have not read anything along the lines of an N54 literally throwing rods, etc. Not saying that it's impossible, as it would clearly be possible on a neglected engine. However I would like to add that the likely hood of that happening, before exhausting all other options, would seem, to me, honestly very unlikely.

If it's a rod, bearing, or anything of that extreme, I'm sure you would notice extreme performance loss or even non-drivability; seeing as how you didn't add that in your initial post, it would lead me to believe that it isn't an issue that is as severe as a rod being thrown.

Does it sound like this?

[e92_boost]

Videos would help out alot. From out you stated its the common issues doesnt effect anything just rattling noise from the Wastegates. If its the Wastegates you sre still covered from factory warranty up to 82k on the wastegates.

[Fundguy1]

Sounds like waste gates to me also from the description. A bad lower wouldn't make noise at only a small rpm range typically. Have dealer #1 replace the turbo setup which includes the waste gates and see if this solves the issue. If it doesn't get the new motor. No reason at 75k it should have been running low on oil. Oil changes are free first 60k and it lasts about 15k per change. All kinds of lights will come on if it's low too.

[Jaronbwall]

Originally Posted by e92_boost

Videos would help out alot. From out you stated its the common issues doesnt effect anything just rattling noise from the Wastegates. If its the Wastegates you sre still covered from factory warranty up to 82k on the wastegates.

+1 Waste gates - hit up that dealership and have the mechanic take it for a test drive.

[Fundguy1]

It's about the right time for original waste gates to give up the ghost, they're changed free under warranty, revised version doesn't go bad, and symptoms sounds like it's them.

[csu87]

if the dealer gave you 30days/1000miles, take it to them, tell them to fix it or you want to return it.

I bet they will fix it.

[agustincuenca]

Thanks all for the replays.
I will be going to the dealer (official BMW here in St Louis) to give them back the car.
I've checked how the wastegate issue sounds and looks like and it doesn't look to be it.
The mechanic that checked the car stated that there is a knock coming from the lower part of the engine present over 2,000 rpm. They haven't opened the engine but from their experience they said was the rod or something deep inside there.
Will keep you all posted.

thanks again!

[Jeff@TopGearSolutions]

Crank bearing possibly. Take it in ASAP for warranty and full diagnosis.

Would like to a hear a video if you could.

[Mike@N54Tuning.com]

Take it back to the dealer you bought from. Not sure what kind of warranty they offered but have them fix. What you describe does not sound like wastegate rattle.

Mike

[GWerks]

Just take the car back to where you bought it and see what they will do for you.

[agustincuenca]

Yes, just went to the Dealer, left the report of the issue from the other mechanic and they will call me after talking to the owner of the dealership. Of course I will make the fix it or change it for another car.
I recorded a video on the highway and will record another one on the parking lot of my house later tonigh and will upload them both.

thanks.

[924er]

There are been many cases of n54 rod spins just google it guys.

[chinko]

Most important would be to take it back ASAP, otherwise you risk not being covered by the warranty. Once they know and make a report on paper, you can research

[agustincuenca]

here's the video. I know it's upside down and the sound is not the best (I crashed my phone last weekend at a party)....but I think it shows the noise pretty clear.

[u2b]https://youtu.be/sAl59-lMI8A[/u2b]

[Fundguy1]

Doesn't sound cool. I have rattling cats and waste gates. Nothing sounding like that. That sounds like a hammer hitting a chunk of steel underwater. Not good.

[agustincuenca]

sorry about my video posting skills...but I found a video that is better recorded and sounds exactly like my issue is. Just confirms that the engine is gone although it had a clean carfax record showing regular oil changes.
I will continue with the dealer, they will fix is at their own expense.

Thanks to all the comments!

[agustincuenca]

Couple of questions:
How long can you drive the car under this conditions?
Is there any other alternative rather than changing the engine? Like a cheap fix? I want to make sure I don't get that....

[924er]

Not sure if I'm fully understanding, you have a warranty that runs out in 4 days(now 2) but u rather open a online forum thread and create a video about it rather than going back to the dealer and get it fixed?

If u have a warranty use it. Don't ask us what your options are whether you will get a refund or if they fix it. Just have them fix it and replace the engine. Go now!

Idk about it is but it sounds like a spun rod to me. It's a common problem with the n54 when you have a leaky injector that mixes with the oil.

[agustincuenca]

Originally Posted by 924er

Not sure if I'm fully understanding, you have a warranty that runs out in 4 days(now 2) but u rather open a online forum thread and create a video about it rather than going back to the dealer and get it fixed?

If u have a warranty use it. Don't ask us what your options are whether you will get a refund or if they fix it. Just have them fix it and replace the engine. Go now!

Idk about it is but it sounds like a spun rod to me. It's a common problem with the n54 when you have a leaky injector that mixes with the oil.

Uderstood. The car is back at the dealer and they are checking it and today I will hear from them whether is a refund or an engine change. In the meantime I was curious and wanted to hear from someone that have been through same issue with the engine.

[924er]

Originally Posted by agustincuenca

Uderstood. The car is back at the dealer and they are checking it and today I will hear from them whether is a refund or an engine change. In the meantime I was curious and wanted to hear from someone that have been through same issue with the engine.

If they replace it you should be good. It's a rare issue, I know I said it's common but that is only if fuel mixed with your oil. Who knows how the car was treating you before.

I doubt you'll get your money back but having they replace the engine or rebuild it isn't a bad idea especially since it's from the dealer so they know what they are doing.

[james008]

Had a rod bearing go in my n54. Not common but certainly happens. My replacement has lasted 40,000 and still going but mentally it has and always will bug me. If you can get your money back go for that first. If not make sure you get a good engine with a warranty.