[Derek Mc]

Knowing the nightmare that emerges with the N20, what is the thinking and what are the possible issues seen on the B48 that people have found.

I am only 9K miles and one year, into ownership of a four year lease car that I really plan to buy out but only if it is a better bet than the ill-fated N20 cars.

So tell me the worst

[HarryTee]

Yes, if you'd like the worst: currently the number of b48 and b58 experiencing locked down are in epidemic proportion regardless of age. Keep yours safe, don't exceed the 9k-mile limit.

[Derek Mc]

Originally Posted by HarryTee

Yes, if you'd like the worst: currently the number of b48 and b58 experiencing locked down are in epidemic proportion regardless of age. Keep yours safe, don't exceed the 9k-mile limit.

Like D'uh!!!

If you don't know just say. My car has been garaged since March 23rd 2020, but, in the rest of the world the engines have been in circulation since 2016

[chowser51]

2018 here. 61k miles now. No issues. Probably time for front brakes. I will measure the pads when it warms up. Sensor has not tripped yet.

[lacrimarum]

Last winter I got "drivetrain malfunction" error at cold starts, the mileage was approximately 50k km. If the engine was turned off and started again, the error always went away. Drove to an indy shop for diagnostics, the error was caused by wastegate valve that was not properly opening while the engine was starting, thus ECU was shutting down the turbo. Mechanic manually flipped the wastegate fully open for several times, and the error have not appeared ever since. I guess some dirt made a way to the rod that operates the wastegate, and it was jamming a little and required some extra effort to open.
This March, at the mileage of 75k km, I replaced the radiator that started to rot, but the roads here are extremely salty and dirty during winter, so that should not be an issue in milder climate.
Other than that, the vehicle was flawless in terms of engine and transmission.

[Pauloxxi]

Originally Posted by lacrimarum

Last winter I got "drivetrain malfunction" error at cold starts, the mileage was approximately 50k km. If the engine was turned off and started again, the error always went away. Drove to an indy shop for diagnostics, the error was caused by wastegate valve that was not properly opening while the engine was starting, thus ECU was shutting down the turbo. Mechanic manually flipped the wastegate fully open for several times, and the error have not appeared ever since. I guess some dirt made a way to the rod that operates the wastegate, and it was jamming a little and required some extra effort to open.
This March, at the mileage of 75k km, I replaced the radiator that started to rot, but the roads here are extremely salty and dirty during winter, so that should not be an issue in milder climate.
Other than that, the vehicle was flawless in terms of engine and transmission.

Your issue with radiator corrosion is concerning. I also have lot of salt on the road during the winter time and never saw this in my cars. I kept my E90 for 11 years.
So yor F30 is what 6 years max and the radiator corroded?

[lacrimarum]

Originally Posted by Pabloxxi

Your issue with radiator corrosion is concerning. I also have lot of salt on the road during the winter time and never saw this in my cars. I kept my E90 for 11 years.
So yor F30 is what 6 years max and the radiator corroded?

It was approximately 4.5 years at the moment.
It's not that it was visibly corroded or lost some of its cooling efficiency. But I usually wash the radiators once in 2 years, and this time the guys at the shop warned me that the radiator core seems already weak enough and will probably break and crumble while being pressure washed. So I decided to put a new radiator in advance.

There are some factors that could facilitate and possibly explain a faster corrosion: I don't exaggerate saying that roads are extremely muddy and salty here It can take a half-hour drive in winter to change car's appearence from completety clean to totally greyish-dirty. Thus I never wash my car from November to April, so all the shit that went on radiator stays there for several months, stimulating the corrosive processes. Finally, a fair share of my mileage consists of highways and B-roads, so there were a lot of stone hits (some were severe enough to even break the plastic grille in front of radiators), and they could probably add some damage to radiator core.

That said, I have never read anything about premature radiator corrosion on f30s on our local forums. The second car in our family, 2007 volvo s60, is still driving in same conditions with its original radiator (despite its age it has a mileage comparable to my f30, though). So I suppose that it's possible that the unit on my car was just faulty in terms of corrosion protection.

[Wires]

Originally Posted by Derek Mc

Knowing the nightmare that emerges with the N20, what is the thinking and what are the possible issues seen on the B48 that people have found.

I am only 9K miles and one year, into ownership of a four year lease car that I really plan to buy out but only if it is a better bet than the ill-fated N20 cars.

So tell me the worst

Not sure what you are looking for here. People will tell you issues they had, but NOBODY will tell you that it was fine.

If you're looking for skewed confirmation bias that the product you purchased may have issues, then bravo, you have 100% succeeded.

You could also . There are so many ridiculous threads about "tell me your problems". I'm going to flip it the other way: If you are asking this question, then you bought the wrong car, period. EVERY brand has problems.

[Derek Mc]

Originally Posted by Wires

Not sure what you are looking for here. People will tell you issues they had, but NOBODY will tell you that it was fine.

If you're looking for skewed confirmation bias that the product you purchased may have issues, then bravo, you have 100% succeeded.

You could also . There are so many ridiculous threads about "tell me your problems". I'm going to flip it the other way: If you are asking this question, then you bought the wrong car, period. EVERY brand has problems.

OK I get that but I have owned used and hobby BMW's since the Nikasil issues back in the 90's and by not burying my head in the sand I was aware of what was going on, and avoided buying an e39 528i with a Nikasil slightly lumpy idle,,,

I asked for the very specific reason as all the blurb on here relates to N20, and so far,,,, so far!! very little said about the B48.
The brilliant thing about these forums is that it is a very efficient way to cut through the bullshit of "my car's wonderful it can do 0-60 in a second and a half,,,,, and get to the hard nuts.

I plan to lay out my hard earned, to buy the car out it's lease in just under three years however, if it emerges that it has underlying issues the way the N20 had, I will let it go and move along to a G10 or G20 (as no way will I buy a Beaver face 4 series,,,)

My apologies that my question offends but as a hobby restorer and mechanic, I am specifically seeking the doom & gloom here, with very good reasons.

[HarryTee]

"My apologies that my question offends"
It doesn't offend but is rather silly with "emerging issues" and "nightmare" upfront. That was the reason for my early reply, but my sarcasm was obviously not obvious enough

[Wires]

Well, it's been out for 4+ years, so if you have heard nothing, then there isn't a lot to learn.

[Derek Mc]

Originally Posted by Wires

Well, it's been out for 4+ years, so if you have heard nothing, then there isn't a lot to learn.

True just as the whole Nikasil issue was unknown to all but the most enquiring.

But I'll be sure to never ask a question about a BMW on a BMW board ever again

[Derek Mc]

Originally Posted by HarryTee

"My apologies that my question offends"
It doesn't offend but is rather silly with "emerging issues" and "nightmare" upfront. That was the reason for my early reply, but my sarcasm was obviously not obvious enough

Given that weekly on this very board, owners report catastrophic failures on N20's many of whom,never previously appreciating the potential of the timing chain issue, I thought my question fair and reasonable. I think owners who sadly have an engine let go might use much stronger language than "nightmare" so your right on that score

So where else apart from a BMW model specific board, do you suggest someone seek this information from care to suggest a source?

[Wires]

If you're looking for reliability, find a source that reports reliability on cars. Asking for the 10 people with bad experiences out of 10 million that have had stellar experiences gains you nothing.

If you have seen all these catastrophic failure posts weekly on this forum, then I suppose you just answered your question (if a skewed sample set is what you need).

[cfm56d7b]

B48 is a 4 cylinder engine based on modular design. B58 is essentially B48 with 2 extra cylinders. BMW made a lot of improvements in B48 engine. Worth searching for N20 vs B48.

[Livetodrive]

2016 B58 with almost 50k miles. Other than “slow down, slow down, you’re taking the turn too fast” complaints from the passenger seat area, no engine issues.

[Derek Mc]

Originally Posted by Livetodrive

2016 B58 with almost 50k miles. Other than “slow down, slow down, you’re taking the turn too fast” complaints from the passenger seat area, no engine issues.

Ha ha ha yip brother,,, that's 100% the kind of problem I want to hear about

[Derek Mc]

Originally Posted by Wires

If you're looking for reliability, find a source that reports reliability on cars. Asking for the 10 people with bad experiences out of 10 million that have had stellar experiences gains you nothing.

If you have seen all these catastrophic failure posts weekly on this forum, then I suppose you just answered your question (if a skewed sample set is what you need).

You are missing the point, there are a cross section of owners from stock engines to those with tuning and chipped engines, hard drivers and trailer queens. I am interested to know if the B48 has overcome the devastating issues the N20 has from enthusiasts, owners and this is I thought one of the only places to gauge this.

My 420i is no longer running at 184Hp /290Nm as an example, and knowing how reliable it is guides my thinking on leaving it making 250Hp / 374Nm or toning it down to maybe 220Hp /340Nm, due to a weakness in some component part or other.
I reckon I am in this car for a rather long time as I plan to make it my weekend hobby car once the lease ends.

[Wires]

I think you're missing the point. You are only going to hear from the handful that have issues and not the bazillion that do not. NOBODY posts saying things are "doing fine". There are only rant posts about how the car died and left them stranded.

[Jostack]

I'm pretty new to BMW and did a fair bit of reading before buying a used 2017 340xi. I didn't find anything that stands out as a 'problem'. I've read about oil consumption, but I haven't had that. I'm ready for my second oil change. Bought with 43k in Jan and close to 60k now.

[chowser51]

I'll clarify mine. I only have 6200 miles with BM3 stage 1 so far. Before that was 8500 miles on JB+ set at max.

No issues.

[Derek Mc]

Originally Posted by Wires

I think you're missing the point. You are only going to hear from the handful that have issues and not the bazillion that do not. NOBODY posts saying things are "doing fine". There are only rant posts about how the car died and left them stranded.

And it is that handful I am seeking, I am not having an issue, I don't need to know that, I am looking for the guy for whom the water pump went South, or the MAF failed, the exhaust heat shield come apart and rattles, etc, as once I see the failure I can analyse it in the overall scheme.

Right at the start of the Nikasil issue, people thought it was just a misfire, then they thought it was head gasket failure only when we all started to come together did we find the pattern of short journey cars that didn't get heated properly, petrol washing the oil off the bores, and BINGO! but had we not analysed it, it would have been so very costly, and the introduction of Alusil taken far longer,,,