(2004-2011) Mercedes-Benz CLS 320 CDI Problems And Buyers Guide

The W219/C219 Mercedes-Benz CLS only came with a handful of engines. One of those was the fantastic 320 CDI diesel engine which was perfectly suited for comfortably covering those long highway miles. And that was the intention of this engine, long-distance driving with loads of power and torque. Even though I never owned a CLS with this engine, I still own a W211 E-Class with the exact same engine which gives me some credibility in terms of conveying the problems that these cars experience. Even though we already wrote about the C219 Mercedes CLS problems extensively, we wanted to dedicate an entire article to the 320 CDI which is the most sensible choice out of all the engines. It is not only reliable and much more economic than a CLS 500, but it also features all the power and torque you could ever need in a car like the CLS 4-door coupe. Here are the most common problems.

Mercedes-Benz CLS 320 CDI Problems With The Engine

The W219/C219 CLS came equipped with the OM642 diesel engine which is the successor to the inline 6-cylinder diesel engine found in the early models of the W211 E-Class. The V6 OM642 engine is a great unit but it does come with a set of typical problems. If the engine is properly serviced, there is nothing stopping it from reaching 200,000 miles and more. The key point here is regular maintenance. Here are all the Mercedes-Benz CLS 320 CDI engine problems:

  • Turbo actuator problems and symptoms
  • Timing chain and timing chain tensioner problems
  • TWC temperature sensor malfunctions
  • Increased engine oil level issues (read more about it here)
  • Fuel injector problems (failure, leaks, “Black Death” – see more here)
  • Problems with the PCV (Positive Crankcase Ventilation Valve)
  • Swirl flap actuator problems
  • Leaky O-ring seals on the oil cooler
  • Oil leaks around the Turbocharger
  • Intake manifold carbon deposits (read more about it here)

We explained each of those problems in detail in our review of the OM642 engine!

Mercedes-Benz CLS Common Problems

Alongside those engine problems you also need to be aware of some other issues that are affecting the 2004-2011 Mercedes-Benz CLS 320 CDI. To ensure a comfortable ride, the CLS features various advanced features like the Airmatic suspension, SBC brake pump, and many other electronics. Below are some of the more common problems.

  • Steering problems
  • SBC brake pump failures on early models
  • Airmatic issues and problems
  • Water leak on the fuse box
  • Faulty air pump relay problems
  • 7G Tronic Automatic Transmission problems
  • Air Conditioning problems
  • Various electronic problems
  • Noisy front brakes
  • Sunroof leaks

Read more about these problems in our full review of the Mercedes CLS-Class C219/W219!

Frequently Asked Questions

Is Mercedes-Benz CLS 320 CDI reliable?

Yes, despite its age the Mercedes CLS 320 CDI has proven to be highly reliable. It is of the highest importance that you seek cars with a full-service history. If you get a bad, neglected example of the CLS 320 CDI, you will be overwhelmed with many expensive repairs.

Conclusion And Recap

There are not a lot of cars that are 18 years old and look just as good today then they did in 2004 when the first generation (W219/C219) Mercedes CLS was released. And the best thing about the CLS is the fact that it does not only look good, but it also feels like a car that is much younger than it really is. We want to point out that while the CLS with the 320 CDI engine is reliable, it is highly important that the previous owners took good care of the car. These cars have a large number of expensive-to-repair components, Airmatic air suspension for example. You do not want to be the 3rd owner who is paying for all the mistakes of the 1st and 2nd owners. Trust us. Good luck with your purchase!

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