Mercedes Benz E class is the most profitable product in the brand’s portfolio. Though, the reliability factor saw a decline with the introduction of W210 in the ’90s. Mercedes’s reputation was tarnished and the brand tried hard to recover with W211. It did see an improvement but there was a big, nay, colossal room left.

With the launch of W212 E class, Mercedes Benz saw a rise in its reputation. The car’s engineering was inspired by the Superstar W124. It was all reliability, bespoke engineering and solid structure. Another reason for the brand becoming the ‘good guy’ was its going-green technology called BlueEfficiency. With parts running on an as-needed basis, the car would return better fuel efficiency and emit less CO₂/kg.

All looked bright and green until you came to own one. Though not as problematic as its predecessor, the W211, and W212 still have some common problems that you should know before buying. So, here we go.

Car dies randomly

Failed crankshaft sensor throws DTC P0336 on Mercedes W212. When a crankshaft position sensor fails, the car may exhibit the following symptoms.

• Check engine light comes on
• Crank-no-start condition
• If the engine starts, it may sputter and die
• The engine may stop randomly while driving
• You can start by reading the DTC on your car. For that, you need a good OBD reader or a scanner. It should return a code P0336.

The hardest part of this repair is to get to the failed sensor. The job requires patience and the right tools. It can be done under an hour if you have both. Here is a video guide. Just identify the engine and you should be good to go.

Erratic shifting

By erratic I mean it shifts at about 2.5-3k rpm and the throttle response is imitation of a drunk guy try to walk straight. By things become smooth when you stomp on the accelerator pedal. It launches right and shifting becomes normal (changing gears at red-line).

Most likely the culprit here is MAF sensor. Cleaning it doesn’t work, so just go ahead and buy a new one from either Benz or a reputed after-market brand like Meyle.

Super-stiff steering wheel

This generation of E-class came with EPS aka Electric Power Steering. The force multiplication is done by a motor so that you, the user, wouldn’t have to put in much effort turning this big sedan.

Now, with age, the seal on the motor becomes brittle and water ingress happens. This act pretty much destroys the device and turning the steering wheel becomes a Herculean task.

You are left with three options here – you get the motor repaired, or you get a used one or you go ahead and buy a new unit from Benz.

Transmission shifting only at red-line

Not a common sight because the 722 series transmission has had many updates. And by the year 2010, most of the niggles were sorted. But improvement is a continuous process, there were still some problems left.

If you’ve been noticing that the transmission shifts only at red-line or very high engine speed with a thud, then you may be looking at a failed turbine speed sensor. It is buried inside the transmission housing and is a laborious job. The job is expensive and should be attempted by a professional.

Climate control always blowing cold air

Even after setting the temperature to warm or high, the vents continue to blow cold air. That is a common failure on the W211 and the W212. The reason is a failed Temperature control valve located under the windshield wiper arm

Since it is a Mercedes, the job is not straight. You need to remove plastic trims, wipers blades and some clips. It may take you some time, but the job can be done on a Sunday morning.

On a side note, the problem of lack of warm air can be due to a stuck AC flap on the driver’s side. The flap controls whether or not to let warm air into the vents. An easy fix is to run the AC on the lowest temperature and bump it to the highest setting. Repeat the process several times until the flap gets unstuck.

Leaks

The engine on these cars can leak coolant and oil from various places. Let me point out what leaks from where.

• Coolant leaking from water pump
• Engine oil leaking from the oil filter assembly
• Transmission fluid leaking from cooler into the radiator

Excessive tire wear on the inside

The thrust link on the Mercedes W212 E class minimizes the forward and backward movement of tires under acceleration/braking. When the rubber bushings wear out on the metal links, the movement will exceed the set amount and cause trouble.

If you have never replaced any suspension component, then take it to a mechanic who has. They will surely source the required part too, which is the rubber bushing. Post repair, don’t forget to get the alignment done at a reputed tire shop.

Interior problems

Retracting center console lid

It is not an uncommon sight to see a cup holder cover not returning to its initial position after pressing. The reason is dirt and gunk accumulating in the lid sliding track. You will need to disassemble the cup holder assembly and clean and lubricate the tracks.

Seat stitching

Mercedes with high miles will have worn stitching on the driver seat unless it had seat covers. Get it re-stitched by an upholstery master to replace it with a new seat cover.

Faded wooden trim

In the early iteration of the car (pre-2011), the wooden trim on the dash and doors would fade out pretty quickly. Mercedes fixed it on the later models, but the folks with earlier iterations were stuck.

You can try to polish them and see if lost luster returns or get new trim installed. Or better, vinyl wrap the trim.