Here's Why We Wouldn't Touch An E46 BMW 3

Sep 25, 2023

Produced from 1997 to 2006, the E46 is the fourth generation of the legendary BMW 3 Series, but it has its fair share of flaws.

Why would anyone looking to get a new ride get interested in a 16-year-old German technology? Maybe because it's a 3-Series BMW. Or maybe for same reasons gearheads buy classic cars for daily driving – the hands-on driving experience, the less-complex mechanical features, and the tendency for classics to appreciate. The hunt for a 20-year-old Bimmer reminds us of the complicated relationship between man and machine. It could be about money, sentiments, or anything else.

However, the primary reasons people buy older cars are the cheap insurance and low taxes as well as their reliability and straightforward mechanical and design features. It's not always about the upfront cost. When it comes to BMWs, Bimmer fans generally believe the classics have a better build quality from better components, making them easier and cheaper to repair or service.

This belief is rather true until you buy certain models we wouldn't touch with a 10-foot pole. The E46 BMW 3 Series is one such model. It sounds like eating our own words because we already wrote in a different article that "the E46 is, without a doubt, one of the most well-liked BMWs ever produced and the model generation that has had the greatest number of sales in BMW's entire history." However, this article shows why age is not so kind with the E46 and, therefore, best avoided today.

Related: 10 Things You Should Know Before Buying An E46 BMW 3-Series

Everyone that claims to be a BMW fan or enthusiast doesn't slack in their knowledge of the E numbers. Only a few still bother with Marks (in this case, Mk4), so we dare say it's a rite of passage in Bimmer circles to have your E number handy. BMW designated the model code "E46" to the 4th-gen 3-Series range of compact executive cars launched in November 1997 and produced through 2006. They arrived the North American market in 1999 and got sold through 2005.

E46 was the successor to the E36 E-Series cut from production in 2000. The E46 hit the market in a variety of body styles, including hatchback (marketed as the 3-Series Compact), sedan, coupe, convertible, and station wagon (marketed as Touring). Close to three decades later, the E46 still kicks ass in the land of handsome cars, especially when found in great condition. The litany of body styles didn't hit the market at the same time.

Roughly three years after the E46's introduction, BMW rolled out the M3 2-door coupe performance model and followed this up with the convertible flavor the following year, specifically in April 2001. Motivated by BMW's S54 inline-six married to either a 6-speed manual or 6-speed SMG-II automated manual transmission, the M3 was the longing of every gearhead's heart and probably still is.

Unfortunately, we don't see you driving this car happily ever after all these years. It's safe to say we don't feel the same about the E30 (the best E-Series, if you ask us) or even the E46's successor, the E90 BMW 3 Series, especially the 328i. Although BMW phased out the E46 in late 2004, the coupe and convertible models held on until August 2006.

Engine problems aren't the E46's biggest issues, but the problems are worth considering whether you're bent on giving this model a bear hug or touching it with a 10-foot pole. They first came with 1.6- to 2.0-liter BMW M43, N42, and N46 inline-4 petrol engines, with available 2.0- to 3.2-liter BMW M52, M54, and S54 straight-six petrol engines. These were later followed by a 2.0-liter BMW M47 inline-4 diesel engine and an available 2.9- to 3.0-liter M57 inline-six diesel engine.

The diesel models were the 318d, 320d, and 330d E46 BMW 3-Series with 114 to 201 horsepower and 195 to 302 lb-ft of torque. The M54 and M52 petrol straight-sixes were prone to PVC (Positive Crankcase Ventilation) failure and clogging.

As Dells Service Center explained, if your positive crankcase ventilation valve stays stuck or clogged, it will cause pressure build-up and oil leakage and eventually break down your engine from sludge production and overheating. Your engine cannot function properly unless all the surrounding parts are doing their job.

Also, the E46 BMW 320i, 325i, and 330i (petrol models) used double Vanos engines with known reliability issues. As you already know, Vanos is short for Variable Nockenwellen Steuerung, which is German for variable timing valve. It was first seen with the M50 straight-six on the E34 BMW 5 Series. The system has spawned multiple variations since its introduction in the early 1990s but in this case, the defective Vanos seals caused considerably less torque and uneven power delivery in the lower RPM range (below 3000).

Replacing them isn't exactly a walk in the park but presents a perfect opportunity to replace the valve cover gasket too.

Let's put a pin on the E46's petrol engine and talk about the diesel models. Even fifteen years ago, the diesel options were reliable mills with proper care but still not the better of the two. The E46 330d's impressive performance is proof of this. However, it's a matter of time before the intake manifold's plastic swirl flaps begin to fail, detach, or get sucked into the engine.

Most people just get rid of the thing to avoid the headache altogether after years of manifold congestion. All the diesel models shared a common problem where the EGR valves got clogged and led to the turbocharger or even engine failure, while the 320d and 330d were also prone to Mass Air Flow sensor failure. We might add that the E46 diesel models suffered from rear axle issues due to the amount of torque produced by the diesel engines.

Related: 10 BMWs That'll Soon Be Worth A Fortune

We said earlier that the engine isn't the E46's most serious problem because that honor goes to the rear subframe mounts. All the E46 models suffered from this problem as long as they encountered snow, salt water, or just moisture. It's a particularly serious one because a failing – cracked or torn – subframe mount effectively makes the car unsafe to drive because it could shift while driving.

The defective subframe mount, with symptoms including excessive vibration, heightened wear of shock absorbers, uneven tire wear, and strange noises, could also lead to other problems, and repairs are neither cheap nor easy. The problematic subframe mounts are to blame for the E46's reputation for weak rear strut mounts.

Summarily, the E46 BMW 3 Series is one of the finest 3-Series BMWs only if this were fifteen years ago. Some people and things age rather badly which, sadly, is the case with this BMW model, even if it never lost its cosmetic charm after all these years. If you insist on buying the E46 today, you’d be wise to brace for a litany of bank-draining problems that space didn't allow us to list here, including the notorious SMG gearbox.

Sources: BMW, Dells Service Center, Life on Four

Philip Uwaoma, this bearded black male from Nigeria, has written more than two million words in articles published on various websites, including toylist.com, rehabaid.com, and autoquarterly.com. After not getting credit for his work on Auto Quarterly, Philip is now convinced that ghostwriting sucks. He has no dog, no wife- yet- and he loves Rolls Royce a little too much.