What Are Common BMW N54 Engine Problems? (And How to Fix Them)
Photo by Christian Wiediger on Unsplash Nobody buys a BMW 335i, 135i or 535i expecting a quiet life. You buy one because it's properly quick, sounds fantastic, and, if you ever get curious about what lurks beneath that bonnet, turns out to be one of the most tuneable engines BMW has ever produced. Three hundred horsepower from the factory, and with a modest tune, you're looking at four hundred without breaking a sweat. The N54 also leaks oil like a sieve, eats fuel pumps for breakfast, and will rattle at you from the turbos until you either fix it or learn to live with the noise. It shipped with fuel injectors, which BMW quietly revised multiple times because the originals weren't up to scratch. The BMW water pump is electric, which sounds clever until it produces problems. That's the deal with the N54. You know this going in, or you find out the hard way. Either way, this guide tells you what to watch for, what it means when something goes wrong, and what to do abou...
