Common problems with BMW 420d

BMW 420d

The BMW 420d is a sleek and well-performing compact luxury car. It comes in coupe, convertible, and liftback body styles. So, users have a variety of options to choose from. But what are the common problems with the BMW 420d? 

Common problems with the BMW 420d are clogged DPF & EGR valves, faulty EGR coolers, crankshaft position sensor issues, and premature engine crank failure. Furthermore, other owners have reported having faulty adjustable rear suspension, EGR system leaks, automatic transmission problems, and faulty air conditioners.  

What are the common problems with BMW 420d? 

Clogged EGR valve 

This is a major problem for BMW 420d owners. Many owners complained that their EGR valves clogged, leading to loss of power, and high fuel consumption and the engine may stall while idling. Note that this issue is normally caused by a car that is driven for short distances. 

To help fix this issue, you should have the EGR valves checked and cleaned if necessary. But if they are damaged, they should be changed. Besides, the driver must drive for long distances to avoid this issue. 

EGR system leaks

This issue is common in the 2014 to 2018 BMW 420d model years. It forced the manufacturer to recall the affected cars and the problem was fixed. Owners stated that an undetected EGR System leaks and may lead to thermal activity in the intake manifold. 

  Who makes BMW oil?

The good news is that the affected cars were recalled and the issue was resolved. This issue was fixed by the engine management control unit being programmed with better software incorporating the most recent OBD functionality.   

Clogged DPF filters 

Apart from clogged EGR valves, owners have also complained about having clogged DPF filters. Clogged DPF filters will lead to poor performance and high fuel usage. To fix this issue, the owner will have to clean the clogged filters or replace them with new ones if they are damaged. 

Faulty EGR coolers 

Another issue that caused BMW to recall some affected cars is the EGR cooler becoming faulty. As a result, it could lead to intake manifold damage and even cause a fire. Nonetheless, fixing this issue is easy as you will have to replace the faulty EGR cooler. Besides, the manufacturer recalled the affected cars (2013 to 2014 BMW 4-Series model years) and the issue was fixed. 

Automatic transmission problems 

Even though automatic transmissions in the BMW 420d have no common issues, it is very sensitive and requires regular oil and filter changes. So, if you don’t take good care of your car, it may develop transmission issues such as jerking and downshifting. 

Crankshaft position sensor issues 

This issue is common in the 2014 and 2018 BMW 4-series models. When the sensor fails, it may send false signals or even cause the engine to enter “limp” mode and limit the power output to prevent potential engine damage. 

This issue can be fixed by updating the software or repairing the VANOS system and crankshaft. 

Faulty adjustable rear suspension

While suspension problems are not very common on the BMW 420d, some owners have still reported them. Suspension issues are common in models with electronically adjustable suspension. Nonetheless, owners can avoid suspension issues by taking good care of the car. 

  Common problems with the Fiat 124 Spider

Faulty air conditioner 

If the A/C on your BMW 420d is not blowing hot air or working properly, it may be due to a bad compressor or freon leak. But in some cases, it may be due to a bad compressor belt or a dirty cabin filter. 

To fix this issue, you will have to clean the dirty cabin filter or fix or replace the affected parts. 

Premature engine crank failure 

There are several problems that cause the engine to fail prematurely in the BMW 420d. Some of these problems include water pump failure, leaking oil filter housing gasket, leaking plastic cooling parts, and leaking valve cover gasket. 

Fixing these issues in time will avoid many engine issues, such as premature engine crank failure, and much more. 


Is BMW 420d reliable?

Yes, the BMW 420d is quite a reliable car. However, it falls below average in most reliability ratings. This is mainly because of the several issues that owners report about. On top of that, maintaining this car is expensive and so are its spare parts. 

Is it expensive to maintain the BMW 420d?

Maintaining the BMW 420d is not cheap. However, it is slightly costlier than maintaining other BMW series like the 5 and 6 series. On average, the owner should expect to spend between $536 and $1,800 per year. Besides, they may also experience major services that may cost between $1,000 and $3,000 in a single visit to a repair center. 

How many miles does the BMW 420d last?

BMW makes some of the most durable and reliable luxury cars on the market. Even though this brand had a bad reputation for reliability in the past, this has improved a lot in the past few years. Besides, the BMW 420d is among the most reliable BMW models on the market. With good care and maintenance, this car should clock more than 200k miles. 

  VW 1.8 TSI Engine Problems

What is the most reliable BMW 420d model?

BMW 420d is one of the most reliable BMW models on the market. With that said, not all BMW 420d model years are reliable. For instance, the 2014 BMW 420d is the least reliable model year, while the 2021 and 2022 BMW 420d model years are some of the most reliable in the lineup. 

Which BMW 4 Series is the best?

It depends on what you’re looking for. If you’re in the market for a fuel-efficient and low-maintenance 4-Series, the BMW 420d SE is the best. But when it comes to great performance and exceptional driving, the BMW 440i M Sport is the best. Finally, the BMW 4-Series 420i Luxury is the best for equipment and comfort.  


The BMW 420d may be a sleek and well-performing car, but it also comes with multiple issues that owners should take note of. Some of the key issues with this model are clogged EGR Valves and DPF, automatic transmission issues, faulty air conditioners, EGR system leaks, and crankshaft position sensor issues. 

All in all, the BMW 420d is still a reliable and durable car. With proper care and maintenance, this car can last for more than 200k miles or 15 years.  

What to know about BMW problems and issues.
Car weaknesses, problems, issues, errors, disadvantages and realiability.

Edwin Odipo

Why do you love writing about cars? Cars make our lives easy. You can visit your distant friend, relative or even rush to the grocery store a few miles from your home with a lot of ease. Imagine how life was before the invention of cars?? To me, cars are a blessing that made life more convenient.

Recent Posts