Some cars effectively define their class.
Just as the previous 3-series BMW models before it, the BMW E90 continues to deliver the ultimate driving machine experience.
Thanks to efficient dynamics technology, all the e90 engines are among the class leaders for fuel economy and emissions. And the performance ranges from capable to colossal.
But what sets the 3-series apart though is how well it drives. The steering is accurate and communicative, while sublime body control and tenacious grip give it great poise through corners. Admittedly, the suspension is firm and you feel some bumps, but it’s never uncomfortable. As well as being huge fun while driving your favorite back road, the 3-series also makes a great cruiser. Road and suspension noise is well subdued and you barely hear it once you’re on the move.
This car uses glass and panel insulation with top-quality materials and ‘built-to-last’ feel. The standard layout features simple stereo and heater controls but if you specify the optional sat-nav you also get BMWs much improved iDrive controller. Thanks to the good range of seat and steering wheel adjustment, everyone can find a comfortable driving position.
Although some may consider a used BMW to be a huge money pit, it doesn’t need to be like that as long as you know what to look for. Choose a model with the right engine and performing maintenance in time will help you avoid plenty of possible problems.
On the outside, you will hardly find any problems. The paint job is of the highest quality and stands up to any kind of environment. A similar situation is with rust, which is rarely seen on these cars. However, early production cars can have problems with the peeling roof trim and disintegrating rubber trim on the top of the windshield. Luckily, both parts are cheap and easy to replace. Sticking exterior door handles were also common on early cars, but this issue was mostly fixed under warranty.
The interior of the 3-series might seem a bit outdated by today’s standards, but it is mostly well built. Complaints range from various rattles from the dashboard, cup holders or glove box. And sometimes you can hear creaks from the door seals on poor quality roads. However, the biggest issue is with the plastic surface peeling, mainly on the steering wheel, center console and door handles. This problem is more frequent on cars before the face-lift and with the light-colored interior. Another common problem is a failed passenger seat occupancy sensor, which will trigger airbag related errors on the dashboard. While there are emulators on the market, replacing the sensor itself is the only proper solution. Other possible issues are with faulty rear electric window regulators, seized blower motor, and unresponsive electronic steering lock.
This car was available with the regular standard suspension or with the factory sport suspension. Unlike its predecessor, the E46, the fifth-generation 3-series has a relatively rock-solid suspension. The weak points are the sway-bar end links, but these are cheap and easy to replace. There are no noticeable issues with brakes, either, besides normal wear and tear. However, a faulty ABS pump or a broken speed sensor will put the whole ABS system out of action. These cars come with run flat tires from the factory, which many drivers find to be less responsive and comfortable than conventional ones.
Under the hood, there is a choice between several, at that time, newly designed engines. These machines had gigantic shoes to fill in, as they replaced the legendary M54 unit, which was a huge hit in terms of power, durability and tunability. Despite initial criticism and disapproval from fans and some experts, new engines proved to be as reliable as their predecessors. From the petrol engines, the most reliable are the six cylinders with the N51 or N52 engine code, installed in cars badged as 325i, 328i and 330i. A step up in the power is the turbocharged version, coded N54 or N55 in newer versions. You can find it in cars with 335i badge on the trunk lid.
Still, just like any other machine in the world, these engines have several weak spots.
- Leaking oil filter housing gaskets are the most common issue with all E90 engines, and you will hardly find an engine that hasn’t had this problem at some time. There are two gaskets. One between the oil filter housing and engine block, and other between housing and oil cooler. With time, these gaskets become hard and brittle, resulting in an oil leak. Gaskets are not expensive, and changing them is quite easy.
- All E90 engines have variable valve timing, called Vanos. Although the system is reliable, two solenoids that operate valve timing can have problems caused by oil sludging. This will cause running issues, lack of lowend torque and illuminated check engine light. Solenoids can be easily removed and cleaned.
- N52 engines have two DISA flaps, which alter the intake manifold geometry. These flaps can get loose and not seal properly. If left like that, they can even break off and cause major engine damage. Repair sets are available online, but the replacement requires intake manifold removal.
- A valve cover gasket is another potential oil leak spot. When that happens, the oil will drip on the exhaust manifold, causing strong burning smell in the cabin. Leaking gaskets should be replaced without delay, as it can lead to a fire in some extreme cases.
- All six-cylinder engines use an electrical coolant pump, whose speed depends on the engine temperature and load. The electric motor that powers the coolant pump can fail with time, causing engine overheating. Although a new pump is a bit expensive, changing it as a preventive measure on high mileage cars is the best idea.
- In addition to Vanos, these engines use Variable Valve Lift system, called Valvetronic. It uses a stepper motor and a combination of levers to control the amount of intake valve lift. Although it seems complicated, the only usual failure point is the stepper motor itself, which can seize. BMW uses a complex crankcase ventilation system, with a set of separators and a diaphragm that controls the crankcase pressure. If this diaphragm ruptures, large amounts of oil vapor will get into the intake manifold, causing blue smoke from the exhaust and high oil consumption. Although BMW doesn’t sell the diaphragm as a replacement part, there are repair kits available online. Typical repair is a new valve cover.
- Turbocharged engines use a high-pressure fuel injection system, which has two common failure points. One is a high-pressure pump, especially on early models, which causes strong hesitation, lack of power and poor acceleration. Another possible issue is with clogged fuel injectors, which can happen if the car runs on poor quality fuel. In addition, turbochargers can start leaking oil internally, although this is not that common.
- Turbocharged engines also tend to have issues with carbon buildup on the intake valves. Symptoms will include slight stuttering during acceleration. Intake valves and ports should be inspected and the carbon should be removed with a process called walnut blasting.
Related article: Common Problems to the BMW 3-series E90 Electric Water Pump