If you’re looking for a car that will bring a smile to your face every time you start the engine, then this is the car for you; the BMW 135i Coupe. From the instant the 3.0-litre straight-six twin turbo engine springs into life you know that you are in a performance vehicle designed to deliver “Driving Pleasure”.
Select first gear and release the clutch and you will immediately feel the strong push in your back as you squeeze the throttle. Changing up through the six speed gearbox, the acceleration is relentless and the gear-shifts are light and easy. With more than 226kW of power on tap and maximum torque of 400Nm available from 1000-4000rpm, this is a car that is equally at home on race track days as it is tootling around suburbia in peak-hour traffic, without having to shuffle gears all the time.
On the open road there is no need to change down when overtaking, given the ample power and wide torque band the engine offers. The great thing is that there is no turbo lag with the twin-turbo design of the direct fuel injected engine. This twin turbo design was retained for the more recent M-Series vehicles, the 1M and M2, as it clearly provides superior performance. Later models of the 135i had a twin scroll turbo, so if you want the maximum performance, make sure you choose the twin-turbo N54 variant engine.
Handling is another strong point of this “Pocket-Rocket”. Whilst the relatively short wheelbase can make the ride a little jiggly, the car seldom becomes unsettled and almost never loses traction unless the roads are very greasy or the bumps quite large. If it happens, the electronic stability control kicks in to avoid any drama, and if you brake too hard the ABS will make sure there is no lock-up of the huge front ventilated discs with their six-pot calipers, or the rear ventilated disc brakes, stopping the car in a straight line every time while retaining full steering control to avoid any obstacle in your way. This car will make the most inexperienced driver look good.
For the more experienced wheel-man, this is a car that can really be punted along. The steering is well weighted both at low and high speed. The is no vagueness at the straight-ahead position and the car will point into the apex of a corner on command with little or no understeer. Squeeze the throttle mid-corner and you can tighten the radius of the corner on the throttle alone. If you need to tighten it more you can promote some oversteer by lifting off mid-corner. Body roll is well controlled with just enough roll to let the car communicate its limits. Steering response is quick to enable you to correct easily if the car is unsettled by a bump mid corner. Whilst this is not a race car it is one hell of a track-day blast. The smile on your face as you pull off your helmet will confirm just how much fun you have had.
For a performance car, the 135i coupe offers sensible day to day practicality. The steering wheel is fully adjustable and the memory-adjustable electric seats can be adjusted for height, rake, pitch and tilt. The seat squab can be lengthened to provide the desired thigh support, and lumbar support can be adjusted to a driver’s liking. The side bolsters provide great lateral support at all times but can also be adjusted to provide increased side support to hold you in place on high g-force corners, or softened for greater comfort in day-to-day driving. Two sets of preferences can be stored in memory to suit two different drivers, or to store track-day settings and daily drive settings if you are the only driver. The car is supplied with two electronic keys which operate the central locking and boot release. Each key can store the personal settings for a driver, such that the vehicle will adjust all your seating and rear vision mirror positions as soon as you press the unlock button on the key fob, so that the 135i is ready for you by the time you open the door. These things can of course be adjusted manually when you are in the car, or by using one of the two memory preset buttons on the side of your seat.
Practicality is further enhanced by a generous boot and comfortable seating for four adults. Being a two-door coupe, you would expect the front doors to be somewhat longer than on a sedan. However to facilitate ease of access when the car is angle-parked, the side glass on both the passenger and driver’s frameless door will roll half way down to avoid the need to be a contortionist when you are getting in, especially if you are parked in a narrow space. You can further make it easier to get in by depressing the opening button on your remote key and holding it down. This will lower all the windows fully, and if you keep holding it, will open the sunroof – the latter being useful to allow hot-air to exit the vehicle if you have parked in the sun for some time. Pressing the lock button on your remote will reverse the process, first locking all doors and the boot, then winding up all the windows and closing the sunroof. By using your remote you can lock the car and adjust the sunroof and windows so they are slightly open to avoid excess heat build up on a hot day.
Access to the rear seats, as with all two-door cars, is more difficult but is made a little easier, as the whole front seat can be moved forward electrically by depressing a rocker-switch located at the top of the backrest of each front seat. There is also a release located in this position that enables the backrest to be tilted forward. Once your rear-seat passengers are in, just push the backrest to its upright position and press the rocker-switch again to return the seat to its last memory position.
For a small car the boot is huge. It will comfortably take two mid-sized suit cases and two carry-on bags without folding down the split-rear seat backs. And if you are a golfer, like I am, the boot will allow you to carry an electric buggy, and a full size golf bag (which fits across the boot behind the wheel-arches), and still carry four people in comfort. How’s that for practicality? If you are willing to sacrifice one or both your rear seat passengers, you can fold down the rear seat backs. They are split two-thirds and one third. With one of the seat backs folded down, you can carry longer items and still have space for three people.
The only time you might find this car a little impractical is if you have young children who require a baby seat or capsule. Lifting children into the rear seat and strapping them in can be awkward, and if you have to do this several times a day then you will soon be looking for a four-door car. Once the kids are able to get in by themselves and fasten their seat belts without assistance from you, the rear seat works just fine. Similarly if you regularly carry older people or those who have mobility issues, the rear seat of the 135i is not the place for them. Apart from that, anyone under 180cm can feel fine in the back seat, although those who are on the taller side may prefer a little more leg and head room.
The ergonomics of the 135i clearly identify it as a driver’s car. The padded leather steering wheel fits neatly into the palms of your hands to connect you with a beautifully weighted steering setup, and is adjustable for tilt and reach. So many of your frequently used functions are right there on the spokes of the wheel: audio system volume controls; phone answering and call ending; audio track selection and voice command activation. There are also a couple of buttons that can be programmed to functions you use frequently. The voice command system allows you to control many of the functions of the computer; GPS and audio systems that come standard in the 135i.
The usual turn indicators, high beam selector for the automatic lights, and wiper controls for the rain-sensing wipers are on stalks either side of the steering column within fingertip reach, so your hands rarely have to leave the wheel. The 135i also come with cruise control. The cruise control does not need to be switched on before using it. Just pull back on the smaller stalk located on the left of the steering column to lock in a speed. Pushing the stalk forward or pulling it back will increase or decrease the selected cruise speed. To disengage the cruise just move the stalk up or down or touch the brake or depress the clutch. To resume cruise mode you just touch the button on the end of the stalk.
BMW have always had excellent instrument binnacles and displays and the 135i is no exception. Directly in front of the driver are two round dials for speed and RPM. These two larger dials are inset with an oil temp gauge and fuel gauge. Between them are all the warning lights. The white numbering on the black dials is clear and large enough to be easily read, and at night is well illuminated in BMW’s characteristic orange glow.
In the centre of the dashboard is another binnacle that houses the GPS map display, computer read-outs and audio information display. This colour display also shows service information and displays warning situations. Using this display you can check the status of all the key operational parameters of the car and even check your engine oil levels (the 135i does not have a dipstick under the bonnet). One minor irritation with this screen is that it can be difficult to read in bright sun light, as it lacks adjustable contrast, and the shrouding is very shallow allowing sunlight to hit the (thankfully) non-reflective screen.
The navigation system works well, providing both visual instructions and audio instructions of upcoming turns. As with most in-car navigation systems, after some time the maps need updating. With the 135i the only option is to buy a new CD disk, which becomes very expensive as BMW insist on charging a premium for these updates.
Bluetooth integration enables you to sync your phone and address book (up to 1200 entries) with the computer in the car so you can make and receive calls hands-free through the car’s sound system. Other audio functions are automatically muted during phone calls although you still get visual prompts for GPS instructions during a call.
There are also 8 pre-set buttons located below the ventilation and dual climate control system. These buttons can be programmed with just about anything you want: favourite phone numbers, radio stations or navigation destinations, making it fast and convenient to activate your selection.
This brings me to the final convenience and ergonomically helpful feature, the BMW iDrive. BMW were the first to introduce this feature to the motor car. Originally it was a small wheel that could be rotated or rocked side to side or front to back to select various functions available through the cars computer and audio system. The selections appear on the centre display screen so you don’t have to take your eyes off the road. Once you’ve found the function you wanted, you simply pressed down on the wheel to select it. In the 2009 135i, the wheel has been surrounded with a number of preset buttons that allow you to select CD, radio, telephone, or navigation directly. There are three other buttons, one to select the main menu; a back button to return you to a prior function and an option button, that allows you to jump to the sub-menu of the main menu. The addition of these buttons have greatly improved the effectiveness of the iDrive.
The only drawback on this 2009 version of the 135i is that there is no internet connectivity, so if you want to download or play music from your phone or streaming service you have to connect through the auxiliary port using an audio cable. Apple CarPlay and Android Auto only became available in more recent version of the 135i. You can also play music stored on a memory stick by plugging it into the USB port located in the centre console.
The BMW climate control makes the 135 a very pleasant place to be year round. The ventilation and temperature controls work well. Driver and passenger can select their own preferred temperatures. The system can be adjusted to control airflow to the screen, face or foot well as preferred, and the fan speed range is excellent. You never feel that the system is struggling to deliver excellent air volumes to the occupants. Screen demist and rear window demist work well, clearing the windows in a very short time. Through the onboard computer you can dial up preferences such that when you press the Auto button on the climate control, the car takes care of all the heating, cooling and airflow for you without you having to worry about it. It’s all very civilised.
No review of the BMW 135i Coupe would be complete without mentioning the engine. BMW has been making straight six engines for many years and this is one of the best they have ever produced. The inherent balance of a straight six cannot be replicated by the use of balance shafts or other engine cylinder variants. This particular engine, the N54, has been further enhanced by the addition of two small turbos, each feeding three cylinders. Because the turbos are smaller than the usual turbos found on many other cars, they spin-up quickly, so there is no discernible lag when you floor the pedal.
The direct injection system does a terrific job of delivering just the right amount of fuel to balance the volume of air being forced into the cylinder, thereby enhancing power and fuel economy. Sure drive the 135i hard and you will burn more fuel. The car prefers 98 Octane, so fuel cost will be a little higher, but then again anyone buying a performance car like the BMW 135i will gladly pay the extra to be able to experience the exhilaration of this fantastic car and engine combination.
The only downside of this engine – and for that matter most direct fuel injected engines – is that you can get some carbon build-up on the inlet valves if you do a lot of slow low engine speed driving. This happens because there is no fuel hitting the valve heads to wash them as it enters the cylinder.
It is further aggravated by virtue of the fact that the crankcase fumes, which are rich in oil vapour containing hydrocarbons, are recirculated into the inlet manifold, where they can be deposited on the back of the inlet valves. The recommended fix for this (if it happens, and you experience some roughness under hard acceleration) is to use a cleaner that is sprayed into the inlet manifold while the engine is idling. If this doesn’t fix it, and if its really bad, you can get crushed walnut shell delivered under pressure to clean the back of the valve, while the valve is fully closed. Make sure you get someone who is very experienced to do this otherwise you risk walnut shell entering the cylinder and causing more serious problems.
BMW could avoid much of this problem by redesigning the crankcase re-circulation system such that the oil vapour is condensed into a catch tank before it reaches the inlet manifold. This tank could be emptied or replaced at regular service intervals to avoid having problems or experiencing reduced performance due to the oil-contaminated air reducing the octane of the mixture being delivered to the engine.
The other precautionary thing that I would recommend is to take the car for a good blast, and/or rev it out to the red-line in the lower gears several times when you are driving around town, rather than changing up at lower revs. At high revs the inlet valve is open for a shorter duration so there is less time for carbon to build up. This doesn’t stop the process but it will delay the build up. In addition it will remove carbon deposits from forming on the spark-plugs so it has a double benefit. The only cost is using more fuel, which from an environmental standpoint is not a desired outcome.
There is one further issue that has been noted with the direct-injected engines in the BMW family. BMW use an extremely high pressure (700 psi) fuel injection system whereby the pressure forces the injector open when it is delivering its charge into the engine. If, for any reason, the injector valve does not re-seat properly, additional fuel can leak into the cylinder affecting fuel economy and causing the engine to run rich. From a performance standpoint, whilst this is not noticeable when the car is at running temperature (as the extra fuel ends up being burnt) it does become a problem when the engine is switched off. Because the fuel injection system retains residual pressure after the motor is switched off, a poorly-seated injector will cause raw fuel to build-up in the affected cylinder, particularly overnight. When the engine is started after this has occurred, the cylinder that has experienced the fuel build up will not fire correctly and the motor runs rough until it’s up to temperature.
The raw fuel also gets into the exhaust system where it can have a deleterious effect on the catalyser. In extreme circumstance the catalyser may need to be replaced – not a cheap exercise.
The only fix for this problem is to replace the faulty injector. Unfortunately BMW, in an effort to fix this problem with its injectors, has gone through several versions of the injectors being used or installed during production and do not recommend mixing injector types. This means when one injector goes faulty, all six need to be replaced. Again not a cheap exercise.
If you are lucky and are still covered by warranty, that’s great. But if you are out of warranty, push BMW to come to the party, especially if your vehicle had very low mileage. You really shouldn’t have this kind of problem in a vehicle that has done fewer than 100,000 kilometres.
Notwithstanding these couple of irritating issues, which in all likelihood few owners will experience, this is a gem of a motor in a fantastic package.
So if you want a car that performs well, is practical and great fun to drive I can recommend the BMW 135i Coupe.