BMW’s N54 engine is legendary among enthusiasts and has received critical acclaim. Today, we explore the pros and cons of finding and owning a BMW with an N54 engine.
Since its introduction in the mid-2000s, BMW’s twin-turbocharged, inline six-cylinder N54 has garnered its fair share of both fanatic promoters and disenchanted detractors.
Most owners praise its best-in-class power from the factory and responsiveness to even moderate levels of modification. But, just as many lament its often poor levels of reliability, citing the numerous recalls and known failure points.
Today, we’ll drill down a little further into one of the most infamous BMW engines of all time: the N54.
What Cars Received the N54 Engine?
The N54 engine first found a home in the 2007 335i. BMW promised from the factory 302 hp and 295 lb.-ft. of torque, but independent testing has estimated the power to be closer to over 310. Backing those claims up is the fact that later versions of the N54 received a factory quoted 335 hp and 369 lb.-ft. of torque, found in the BMW Z4 sDr35is and the 335is.
But there were more than two iterations of the N54, and many different body styles to choose from. In fact, a car regularly hailed as one of the best-driving BMWs of all time by sources like Car and Driver, the BMW 1M even utilized this engine in its more aggressive form shared with the aforementioned 35is-designated cars.
Here’s what you can buy in the United States if you’re trying to get into an N54-powered BMW:
- 2007-2010 335i
- 2007-2010 535i
- 2008-2010 135i
- 2008-2010 X6 xDrive35i
- 2011-2012 740i
- 2009-2016 Z4 sDrive35i
- 2011-2013 335is
- 2011 1 Series M Coupe
Of course, there were a number of different trims and options offered alongside each model. You could get a touring/wagon version of the 535, and the 3 and 5 Series were both also available in xDrive (BMW’s all-wheel-drive system).
Notably, the 1M listed will set you back close to $40,000 on the low end, while early N54-powered 335i and 535i will usually come in at under $10,000. Regardless of budget and body style goal, there’s an N54 car for almost everyone.
N54 Reliability and Recalls
The N54 is a very highly regarded engine, for the most part. It’s received numerous International Engine of the Year awards and had thrice won the Ward’s 10 Best Engine Award.
From an enthusiast standpoint, there are few engines today that can offer a similar return on the dollar in terms of modifications. A few simple mods can easily get you closer to 500 horsepower without breaking a sweat, which we’ll discuss later.
However, the N54 does have its fair share of problems. Most common are the ones that BMW itself had to take corrective action on. Most infamous are the high-pressure fuel pump (HPFP) and fuel injector recalls. The former entails a class-action lawsuit and warranty extension, and the latter requires both a warranty extension and redesigned part.
It doesn’t stop there, though. The N54 also suffered from premature wastegate rattle. Essentially, the valve that moderates exhaust flow into the turbocharger will fail prematurely–with some regularity. Enough regularity, in fact, to force BMW to extend the warranty on these components too, but only in the U.S.
Other well-documented failure points include, well, most of the engine’s components. Premature carbon buildup in the intake valves can lead to many different problems, and requires a “walnut blasting” somewhat regularly. The valve cover gaskets, and even the valve cover itself, will usually start leak oil and require replacement.
And like any good BMW engine, the water pump and thermostat are basically regular maintenance items.
Despite a higher than average number of common failure points, the N54 engine promises a unique and thrilling driving experience.
If you can’t spot the common failure points yourself, a pre-purchase inspection is highly recommended. It’s very important to know what you’re getting into, and for this reason, the N54 is a favorite among hands-on enthusiasts and DIY-ers. The wrong N54-powered car can be extremely expensive to maintain if you aren’t doing the work yourself or have a trusted mechanic.
Dealer prices on even the mildest repairs will rarely be less than four figures. Save yourself the headache, err on the side of caution, and buy the right car first.
N54 Power and Potential
Perhaps the crowning achievement of the N54 engine is its nearly unrivaled ability to handle aftermarket additions and promise a huge return, even on relatively inexpensive modifications.
Simply removing the catalytic converters and upgrading the intercooler will net you a nearly 100 horsepower increase — and that’s using an “off-the-shelf” (OTS) tune.
MHD Tuning promises 420 horsepower just off those simple modifications, and that’s before you even delve into the world of alternative fueling.
With alternative fuels (primarily, high-ethanol content fuels or methanol), you’ll be able to reliably generate close to 500 horsepower on these cars. You can safely run ethanol on stock hardware (up to about 40% ethanol content). But, if you choose to upgrade the fueling system (notably, the fuel pump and fuel rail), you can rest assured that you’ll be making very near 500 horsepower at the crank.
Not bad for a fairly minimal investment. Similar setups will cost under $2,000 and are extremely common in the N54 community.
Of course, the quest for power doesn’t have to stop there. The N54’s power truly comes to light when you start making major supporting upgrades, like the turbos and the fueling system–there’s numerous well-documented 600-plus horsepower examples running around, and current record-holders float right around 900 hp.
Naturally, this requires a little bit more cash, but the beautiful thing about the N54 engine is its versatility. You can spend as much as you want and get a real powerhouse, or keep it more budget-friendly and still have a properly fast BMW.
Which N54-powered BMW is the Best Buy?
As mentioned earlier, the nice thing about trying to buy an N54-powered BMW is that there’s a spot in every budget for it. The BMW 1M is a highly-desirable and fairly-rare collectible, with prices ranging from $40,000 to close to six figures, depending on miles and condition.
By contrast, an early model 335i or 135i will typically run you under $10,000. Somewhere in the middle exists the 35is cars, which are reasonably rare and sought after.
[Quick tip: Instead of using a traditional torque-converter transmission, the automatic option in these cars is in fact a dual-clutch unit lifted straight out of the M3. This means lightning fast shifts–up or down. These cars will trade well above $10,000, and will likely also hold value well due to their “specialness.”]But, no matter what price point or configuration you’re looking at, there’s an N54 car out there for you. The Z4 promises RWD roadster fun, while the 535xi wagon offers a super-practical, AWD family option that you can also modify to your heart’s content.
The sky’s the limit with this platform. Just make sure to do your research before you jump into anything.
Photos: BMW
