From 2004 to 2015, the BMW N52 was a naturally aspirated straight-six petrol engine. The N52 made its début on the E90 3 Series and E63 6 Series, taking the place of the BMW M54.
The N52 was the first water-cooled engine with an engine block made of a composite of magnesium and aluminum. Additionally, in 2006 and 2007, it was named one of Ward’s 10 Best Engines.
The BMW N53 was introduced in 2007, and this caused the N52 to start being phased out in European markets. However, because of the high quantities of sulfur in the gasoline, the N53 was ruled inappropriate in markets like those in the United States, Canada, Australia, and Malaysia. The BMW N20 turbocharged four-cylinder engine started to replace the N52 in 2011 and continued doing so until the N52’s manufacture ceased in 2015.
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Failure of VANOS
The N52 has double VANOS, BMW’s variable valve timing technology for the intake and exhaust valves. The system uses VANOS solenoids to regulate the oil flow to the actuators that turn the cam gears, opening and closing the valves as a result.
The failure of these solenoids was one of the N52’s more frequent issues. Your engine will continue to function in this situation, but you’ll notice a substantial loss of power along with other symptoms like a choppy idle.
Fortunately, replacing the solenoids does not require a lot of money or labor. They typically last for 70,000–75,000 miles, but we advise replacing them on a regular basis to prevent any unanticipated declines in engine performance.
Here Are Some Things You Need To Know About The N52
The N52 was a superb successor to its predecessor, the M54, with toughness and lightness as its strong suits. Due to their small weight, which improved weight distribution, these engines were capable of producing up to 260 horsepower when equipped with double electronic variable valve timing. Add a variable-length intake manifold, and your engine will be producing a sound that is comparable to the renown 2JZ “GE.”
The 2JZ GE had forged internals like conrods and pistons (the GTE had different pistons and head gaskets), whereas the N52 was hesitant to implement any significant forced induction, despite a few pricey supercharger kits that at most extract an additional 50 horsepower.
There is always the possibility to forge the entire unit, of course, if you have the money, but why would you want to do that when you can get a N54, the GTE’s envious rival? The N52 is essentially similar to a meal that is best enjoyed on its own. Null meat. Zero salad. Definitely no gravy, either.
The N52 is among the best sounding inline six engines thanks to its burbles, pops, and bangs, as well as its linear power range. Additionally, it has a special trick that allows it to travel down the highway and return 39 mpg. This may not sound like much, but keep in mind that this engine is also used in the e92 coupe, which can accelerate from a standstill to 60 mph in just six seconds. Not much room for compromise, then.
Everything You Should Know About the BMW N52
For two years in a row, in 2006 and 2007, they received recognition as one of Warda’s ten best engines. With years of experience under their belts, BMW improved several aspects of engine manufacture, and we can claim with certainty that its N52 Engine is one of its most popular and illustrious Engines.
The E90 3 series and E63 6 series introduced the BMW N52, an inline-six petrol engine with naturally aspirated displacement. The X1, E90 325i, 128i, 328i, 330i, and E60 525i and 528i all use N52 engines.
Following the 2006 manufacturing halt of its straight-six ally, the BMW N54, it was produced from 2004 to 2015 and took its place. The N52s were the first aluminum-magnesium composite engine blocks that were water-cooled.
Despite being a superb engine, the BMW N52 was regrettably forced to be phased out in European markets after the introduction of the last straight-six engine, the N53, in 2007.
However, the majority of customers in the United States, Australia, Malaysia, and Canada continue to use its previous model, the N52, due to emission issues including excessive sulfur levels in the gasoline and were unfit for the engine work for the unsolved issue in N53s.
The N20 turbocharged four-cylinder eventually took the place of N52s until its final year of manufacture in 2015. For N52, there are two versions, however this Engine doesn’t have a M version.
A Letter of Love for the BMW N52
Excessive negativity is a disturbing tendency in automotive journalism that has spread like a cancer over the internet automotive community. A new generation of writers has emerged, eager to showcase their talents and establish themselves as deserving of the attention and respect of editors and readers alike. A wall of irony and snark has formed as a result of a postmodern cultural change, a desire to conceal ignorance and inexperience, and something we’ll term pride.
If you visit any automotive website, you’ll probably see a ton of articles with names like “Top 10 Reasons Why That Thing You Like Actually Sucks” or “Why the (insert car/engine/racing series) is Overrated.” The entire industry could benefit from a lot more humility and sincerity. In keeping with that, I won’t discuss the aspects of the N54 engine I dislike in this week’s post. Instead, I’ll talk about why I adore the N52. Maybe by the time it’s through, you’ll realize that you share its love.
A long line of BMW overhead cam, naturally aspirated inline six cylinder engines ended with the N52. That set up represents, in the eyes of many, the classic BMW driving ideal.
The BMW portfolio has evolved along with changing consumer needs and pollution regulations. Although it’s undeniable that BMW’s turbocharged four- and six-cylinder engines provide an excellent combination of power and efficiency, it’s disheartening to think that future generations of first-time BMW owners won’t get the opportunity to feel the inline six’s distinctive draw.
The N52 was similar to many previous BMW inline sixes in that it had an even torque curve with a flat top, in part due to variable valve timing on both camshafts. But what was really amazing was the power production.
The N52B30 was installed in the top-of-the-line, 330i, model of the brand-new, at the time E90 3 Series in 2006 and only in 2006. The 330i produced an astounding 255 horsepower thanks to a new tune and a three-stage intake that set it apart from the 328i that came after it in 2007. Being naturally aspirated, it is the most potent non-M BMW inline six ever created.
The incredible 335i that took its place in 2007 very immediately eclipsed the 330i, making it seem like a one-hit wonder. It was powered by an inline six-turbocharged N54 engine, which was a first for BMW. BMW had already experimented with turbochargers with the fabled 2002 turbo and the E23 745i, but this really gave the people the power.
However, it is unfortunate that the N52’s advantages have mostly been overlooked in the turbocharged wake of the N54. The advantage for enthusiasts like us is that N52 vehicles—even range-topping models like the E90 330i—are quite inexpensive.
The N52 requires little maintenance and requires little food. There aren’t really any significant faults, save for a lifter tick problem with fixes ranging from a BMW recall to “just deal with it.” Replacement may be necessary for the Valvetronic motor and a number of “sometimes permeable” gaskets. Aside from that, a properly maintained N52 may provide you with loyal, trustworthy, and reasonably rapid service for tens of thousands to hundreds of thousands of miles.
I want to express my gratitude to my friend Chuck for allowing me to use pictures of his 2009 328xi in this article. If Chuck is reading this, please go ahead and order the three-stage manifold. You won’t be sorry.
How can I tell what kind of engine my BMW N52 has?
From 2006 to 2015, the engines were put into a wide range of various BMW automobiles. They can be found in the Z and X series, as well as the 1, 3, and 5 Series. Being aware of the type of displacement you’re dealing with is one simple technique to identify which engine you don’t have. N51 was only offered as a 3-liter engine, hence any inline-six of this generation that is 2.5 liters will be N52.
Following that, the following are some of the key variations between the two engines:
- Both the N52 and the N51 use aluminum cylinder heads, but the N51’s is unique due to changes made to the combustion chamber to comply with SULEV regulations. They cannot be switched out.
- Cylinder Head Cover: The cylinder head cover on the N51 is made of plastic and has integrated crankcase ventilation; the one on the N52 is made of magnesium.
- External crankcase vent valve with cyclone separator is a part of the N52’s crankcase ventilation system. The N51 contains an integrated vent valve, a labyrinth, and cyclone oil separation, as was already noted.
- On more powerful variants of the N52, the intake manifold is made of plastic and has a 3-stage DISA valve. The 3-stage DISA unit on N51 is used to account for various compressions.
- Piston/compression Ratio: For N52, this ratio is 10.7:1, but for N51, it is 10:1.
- The N51 utilizes a digital hot film meter, whereas the N52 features an analog version.
The problem is that despite all of these distinctions, it’s impossible to tell these engines apart by just opening the hood. Not like the M56 and M54 generations, for example. You could immediately distinguish the M56 SULEV from the M54 thanks to aesthetic differences.
But there is a solution. Examining the car emissions plate under the hood is the quickest way to figure out which engine you’re working with. The pertinent information can be found in the third row, on the left side of the plate. The N51 has a SULEV tag, but the N52 will be labeled as an LEV.
How can I tell whether my BMW is a N51 or N52?
N51 vs. N52 in BMW Checking the emissions label on the underside of your car’s hood is the simplest way to determine what engine is in it. While the N52 will have “ULEV,” the N51 will say “SULEV.”
BMW N52 has direct injection, right?
There is no direct injection in N52. N52 uses port injection specifically. Since around 1976, BMWs have used port injection. Starting in about 2006–2007, the N53 for Europe and direct injection for turbocharged engines will be available.
How reliable is the N52 engine?
One of the most popular and successful inline-6 engines made by BMW is the N52. The N52 was primarily used in the E90 325i, 328i, and 330i as well as the E60 525i and 528i models. It was also used in a number of other vehicles, such the 128i, X1, and Z4, to name a few. From 2004 until 2015, the N52 was manufactured before being superseded by the turbocharged N20 engine. The M54, which was utilized in a number of E36, E39, and E46 models, was replaced by this model.
BMW was able to refine several parts of the engine during the course of manufacture thanks to the lengthy production history. Even top 10 best engines awards were given to the engine in 2006 and 2007. The N52 still experiences a good number of typical dependability issues, though. We’re going to talk about the top 7 engine problems that the N52 has.
The N52 has proven to be more dependable than its larger sibling, the N54, thanks to the engine design. Drivers of the N52 won’t have to worry about these two typical N54 problems because the N52 lacks an HPFP or direct injection. You may read our tutorial on N54 engine issues to compare the two as well!