[Hiddenknife]

My stock B58 blew up (Yes you read that right). Help me try to figure out what happened

I had only owned my 2018 M240i X-Drive for 2 months, until it blew up. It was a low milage car, one owner, very good condition, well documented service history, 100% stock. I had it serviced at a BMW dealership immediately after I bought it. Drove it carefully, always checked oil temp before getting on it etc.

I was driving home from work one day, went up an on-ramp and gave it some gas. The car got up to third or fourth gear, then started to jolt forward and buck really aggressively, then goes into drivetrain malfunction mode. It has misfires after this, vibrates on idle and runs rough, probably not on all cylinders. Get flashing check engine light during the bucking and then a lasting check engine.

Error codes:

* 120408 - Charging pressure control: Switch-off as consequential reaction.
* 140001 - Combustion misfires, several cylinders: Fuel injection is switched off.
* 140010 - Combustion misfires, several cylinders: detected.
* 140601 - Combustion misfire, cylinder 6: Fuel injection is switched off.
* 140610 - Combustion misfire, cylinder 6: detected

I limped home the last 5 minutes (I was almost home). This happened during rush hour on a SINGLE lane highway (Yes, those exist outside of America) with a shoulder only big enough to let a Kia Picanto go past. I felt that it would be way too dangerous for me to stop.

Still had warranty on the car from where I bought it, they ordered me to take it to a shop. Had it towed there.

The shop replaced all 6 sparkplugs, the car did not misfire instantly upon startup anymore. Probably because the old plugs was completly covered in oil I assume (You'll know why soon). I got the car back and went out for a test-drive immediately to make sure it was fixed, it was not. Exact same issue after the first "pull". Drivetrain malfunction and misfires and does not run on all cylinders. No check engine light, did not manage to scan the codes the second time since I just dropped it off again.

The car then sat for at this shop for 4 weeks with no one touching it, they said the car would not start anymore. Battery was good, did not crank.

I demanded the car to be towed to a BMW dealership that knew what they were doing. The BMW techs looked at it and figured out why it would not start, Cylinder 6 was FULL of oil. They could spin the engine by hand backwards until it stopped, then forward again until it stopped. The cylinder could not compress the oil in the cylinder, thats why it would not turn over.

They pumped out all the oil in the cylinder, and then the car would start up and bellow out tons of smoke from all the oil that burned off. After a while sat at idle, it would stop smoking and behave normally. The BMW techs said some PVC part was the problem.

They replaced the PCV-Valve AND the Valve cover gasket on a friday, the car then sat over the weekend, on tuesday they had to move the car. When they started up the car it spewed out tons of smoke, once again.

After this the BMW dealership ruled out the engine in the car and said it needed to be replaced. They've had a specialist look at it.

I still had warranty left on the car from where I bought it, and this whole repair process had been going on for way too long (This is a very shortened version of it all) and the car was still not fixed. After alot of back and forth of me demaning to have the car refunded, I was eventually granted this and got my money back. The car ended up getting a new engine and then sold to someone else. (Verified this with the next owner).

I also had transmission issues with the ZF8 that it not always wanted to shift on it's own, but would shift if I commanded it via the paddles. I just wanted to get rid of the car and we did not even get to this part.

Anyone more educated have any clue what happened to this machine?

This was my first BMW, and I specifically sought out for the B58 because of it's reliablity. Found a good example (I thought) and it blew up, so I think I have a BMW cooldown a while now while I think on where to go next..

Recently read this post on reddits BMW Tech and had me worried about B58s overhype regarding reliability. What are your thoughts?

[Pentland]

Millions of B58s sold. You have no idea of the history of this specific vehicle.
I don’t think there is “overhype” of the B58 over any other engine.

[Rdurty2]

You probably shouldn’t buy any car then. This has happened to every make and model on the road.

Dig out your bicycle

[Littlecoupe]

Something to consider, for however you choose to interpret it, is the fact that Toyota did a lot of scrutiny on BMW's drivetrain (the B58 and likely the ZF) before officially considering up to their quality and reliability standards when using it for the Supra. Granted, I would argue modern car reliability isn't the same as a late 80's/early 90's Toyota or Honda which seemingly ran forever, but if Toyota is willing to put their "quality" reputation on the line using the B58, it must be decent in their view.

Also, the OP's referenced post is a 2018, the gen 1 B58, whereas the G42 is running the B58TU. For better or worse? Time will tell. At least we don't have the B58TU2, sounds like there are some kinks to be ironed out with that newest iteration.

Regardless, a BMW is simply going to cost more to fix on average when it does break. Will it break more often? Hard to say. Lots of original B58 owners claiming they make it past 100K miles without any notable service, besides a couple typical points that should have been less than $1000 for a repair. I'd consider that good in the realm of luxury cars.

[rons e92]

Seems like it was a used car. Here's some food for thought.

When I went to potentially buy my M2, I took my M240i to the dealership. The car was modified, it was lowered, had apex wheels, intake, downpipe, jb4. The car was drag raced and roll raced. I was clear about this as they CAs were drooling over my car. They ended up giving me $5k over book value for the car. I turned it in for trade completely stock.

That dealership then turned around and sold my car as a CPO car. They knew it was modded, they knew I turned the boost up and texted the car, and still they sold it CPO to someone from Rye, NY.

I tried to find this person to tell them so they could ensure they had protection of something were to ever happen, but I was unsuccessful.

And to be totally honest, I tried many settings with that JB4. It never felt right to me.

[Littlecoupe]

Originally Posted by rons e92

Seems like it was a used car. Here's some food for thought.

When I went to potentially buy my M2, I took my M240i to the dealership. The car was modified, it was lowered, had apex wheels, intake, downpipe, jb4. The car was drag raced and roll raced. I was clear about this as they CAs were drooling over my car. They ended up giving me $5k over book value for the car. I turned it in for trade completely stock.

That dealership then turned around and sold my car as a CPO car. They knew it was modded, they knew I turned the boost up and texted the car, and still they sold it CPO to someone from Rye, NY.

I tried to find this person to tell them so they could ensure they had protection of something were to ever happen, but I was unsuccessful.

And to be totally honest, I tried many settings with that JB4. It never felt right to me.

Not a BMW, but I have a similar type of story. I had a supercharged Pontiac Grand Prix with minor mods - downpipe, DIY intake and PCU primarily. I did a lot of research into modding but didn't pull the trigger, not even a smaller pulley. I sold the car to a younger guy, explained what was on the car and very specifically warned him if he is modding, he needs the supporting mods. Pulley should have colder plugs installed, minimum, and that's just for a slightly undersized. Intercooled if going smaller. Octane is important, intake temps need to be monitored, and the car had up to 4 degrees of knock retard even bone stock on 91 octane, so be forewarned.

I saw my car up on the classifieds a year later (I recognized the wheels and exhaust tips), and it said it had engine damage. I reached out and it was the kid I sold it to, he had engine knock because he put on a pulley that was too small for the lack of supporting mods he did not install. He basically slapped on the smaller pulley and eventually blew the engine, even though I warned him specifically not to do that.

The GM L67 Series II is known to be quite stout and reliable (shy of some supercharger specific maintenance), yet the kid blew it up in less than a year. So 1 specific instance of someone killing a B58 shouldn't stand as the norm.

[Dinosoar]

Yeah, not a lot of sympathy on this site, huh? I think you just got unlucky...sorry that happened to you. Upsetting, no doubt! The B58, like most engines these days, is pretty complex. One key component goes bad, it can come apart. But, the point is that the B58 (and the ZF 8-speed behind it) is the industry standard and backed up by numbers. Lighting can't strike twice, get another one!

[Hiddenknife]

Originally Posted by Dinosoar

Yeah, not a lot of sympathy on this site, huh? I think you just got unlucky...sorry that happened to you. Upsetting, no doubt! The B58, like most engines these days, is pretty complex. One key component goes bad, it can come apart. But, the point is that the B58 (and the ZF 8-speed behind it) is the industry standard and backed up by numbers. Lighting can't strike twice, get another one!

its not to me that has happened

[curtdragon]

"Horror" story. Engines break and as someone said, you dont know the history. Someone could have tuned it and put it back to stock. It happens