The BMW B48 Engine

Granted, BMW doesn't exactly have the best track record with four-cylinder engines. However, the (relatively) new B48 engine has been proving itself a pretty sturdy unit. That said, no engine is truly indestructible, and European powertrains do need a little more due care and attention. Maintain it like a German, as they say.

The B48 engines come in many tunes, but in the U.S., the '30' version is most commonly seen. It's installed in a good chunk of BMW models, from the 2 Series Gran Coupe (228i) to the 5 Series (530i). It's also used in a couple of Mini models.

Zac Palmer

Zero Tolerance for Neglect

As (reportedly) reliable as the B48 has been, it becomes especially unhappy at the first signs of neglect. Yes, all engines are like that, but you'll feel it more with these European motors. Case in point, I Do Cars tore down a block from a 2017 230i that suffered a catastrophic failure at about 112,000 miles.

The reason why it blew? It simply didn't have enough oil in it. Now, it's unknown why it was low on oil, but the engine was modified, did a hard pull, and met a violent and explosive end. High revs and little lubrication are, indeed, a combination for disaster and nearly tore up the bottom end of this engine.

A Possible Leak

During the teardown, the engine was already showing signs of leaks around the water pump. That said, it wasn't the main reason for the failure. I Do Cars reckons it was due to an oil leak from the oil filter housing gasket. Still, a low oil level was the main culprit, given the kind of damage the engine sustained.

It could've been prevented by checking the oil level, but it's not exactly a straightforward thing in BMWs these days. With no oil dipstick, the only way to do that is through the infotainment system and trust that the correct level is displayed. We do wish more automakers would bring back the dipstick.

However, assuming it was correct, there should've been signs that something wasn't right with the engine anymore, whether through warning lights on the dashboard or the engine sounding different. Again, it's worth pointing out that the engine was modified. It's a reminder that tuning can increase wear on components, and even more care is needed to keep them healthy, especially when driven hard.

BMW