Over the years, Germany has gained a reputation for creating sturdy, reliable cars that are practically bulletproof. For most people, Germany is the number one source for car reliability. Most cars made in Germany last for years and spend most of their lives on the road. However, some German cars slipped through the cracks, and spend most of their short lives at the garage.

RELATED: 10 High-End Luxury Cars You Can Buy For Cheap

Even the German car manufacturers can get it all wrong. We've seen some of the Japanese cars which will be money pits, sitting in the Garage 24/7. Now it's time to see some of the least reliable German cars.

10  BMW E60 M5

via: Motor1.com
via Motor1.com

The E60 BMW M5 is easily a fan favorite. Powered by a Sauber-derived Formula One S85 5.0 V10, it will hit 60 in 4.2 seconds, topping out at 204 mph. Good examples of this model can be picked up for less than $10,000. However, this car is not at all known for its reliability. It was built during the period where BMWs lacked quality inside and out.

First, the SMG gearbox always caused issues, eating through clutches that were over $2500 to repair. Then there is the fragile engine and its ECU where owners may experience common issues such as engine blow-ups and throttle actuator issues. Lastly, there are the electronics that develop costly glitches as they get older. Worse still, only specialist garages and main dealers can work on the complex sophisticated engine.

9 Porsche 996 Carrera/Carrera 4

The Porsche 996 911 was the worst 911 generation. Almost everything was changed from its predecessor. Its exterior, interior, and engine. Porsche changed the 911 from being an air-cooled car to a water-cooled car. This, its shared development alongside the cheaper 986 Boxster, and its "fried egg-shaped" headlights caused outrage and hatred in the 911 community. The 996 is still the cheapest 911 today.

Related: 15 Porsches You Can Still Pick Up Relatively Cheap

The  3.4 flat-6 engine, offered in the Carrera/Carrera 4, are susceptible to the infamous IMS bearing. If this is not addressed via a $4000 retrofit then expect serious engine failure. There are numerous cooling issues too, with some cars regularly overheating. The 996 was built when Porsche had serious financial issues. This is probably why its build quality was so poor. They didn't even bother to try fixing the IMS bearing.

8 Mercedes M-Class W164

via: autoevolution.com

The Mercedes M-Class was the first Mercedes made in the USA, being a rival not only to the BMW X5 but also to all the American SUVs. When it came to the W164 model Mercedes, like many other car brands, was going through an era of poor build quality. This led the M-Class to continually plunge in value.

Rust is a common issue for this vehicle, and its large body panels mean it's not cheap to repair. The engines are a pain to maintain, especially the gasoline-powered ones. Then there are its awful electronics. Its heated seats tend to short out, killing the heater altogether, and making the seat very hot. None of this is cheap to repair since OEM parts and labor costs are sky-high.

7 BMW E9x 335i

via drive-my.com

The 335i is a good example of why not to buy a used BMW  A fan favorite, it had one of the best, turbocharged engines- the N54 but it was probably also the most unreliable. This car seems a great buy at ridiculously low prices. A perfectly smooth, sporty 3.0 daily then? Wait till you've owned one for a few weeks.

There are many "common faults" with this car. Forums such as Bimmerfest always call the 335i "unreliable," with many owners experience problems a few months into ownership. Turbo issues and ABS  issues are common. Most owners are advised to learn basic mechanical skills when they purchase a 335i, as it has so many problems.

6 VW Phaeton

Via: Pinterest

Buy any Phaeton and you'll encounter issues.  The Phaeton was a sales disaster for VW, trying to make a luxury car from the brand known as the "people's car." It didn't make any sense. While the car is cheap second-hand, repairs are not.

VW  has recalled the Phaeton a few times. Engines such as the 3.0 Diesel may be pretty strong, but the W12 or the V10 TDI are not. The W12 was used in the Bentley Continental, so it has sky-high maintenance fees. The V10 is also quite tricky to work on, meaning labor costs are high. Electronics tend to go wrong on these cars. In an Autocar review, the Phaeton scored 2/5 stars.

5 BMW E65 7 Series

Via: formtrends.com

The E65 BMW 7-Series is what happens when you "over-engineer" a car. Autotrader described the E65 7 series as  "the most hated BMW in the USA." The technology was far ahead of its time, which caused reliability issues. Its electronics tend to be temperamental, especially the complex "iDrive" system.

Related:15 Ultra-Luxurious Cars we'd Buy Over The BMW 7-series

Owners on Bimmerfest, tend to complain about its electronics and the complexity of this car. Be prepared to spend over $1000 for minor issues.

4 Audi R8 Type 42

via: drivemy.com

The R8 was Audi's first supercar and it was a huge success as the car of choice for Tony Stark (Iron Man). However, it's not as reliable as you may think.

Although the car is built very well, it's very complex. Its bodywork is expensive to repair. The clutch wears out very easily on the R-Tronic models but this isn't so common on the manual or S-Tronic cars. To repair the clutch you need $1900, plus labor costs. Then there is the $1100 lightweight battery, which will go flat if you leave the lights on, plus the magnetic suspension can also play up.

This car requires a specialist or a dealer's attention, so the R8 may seem like a supercar on a budget, but parts and labor are expensive here.

3 Mercedes S-Class W220

via mercedes-enthusiasts.co.uk

The W220 was made when Mercedes were cost-cutting for more profit. The car was no longer handbuilt and quality was lacking everywhere, hence its poor residual value.

The W220 suffers from rust, due to poor water-based paintwork. This is a common and expensive issue. Its airmatic suspension is also very problematic since the pump can leak very easily. Then there are the awful electronics! Similar to the E65 7-series, this car is full of tech. This leads to an array of issues including the radio or cluster lights staying on which can lead to the battery being drained.

2 Mercedes CLA C117

via:wheelfront.com

The Mercedes CLA was built-in Hungary and lacked quality is many areas. There has been numerous safety recalls since the CLA was released in 2013, including four airbag-related issues.

Common issues include the display failing to work, stalling on the stop/start function, interior rattling, loss of power, and multiple leaks. You can see most of these in the CLA forum. These cars will spend a lot of time in the garage, fixing little niggles and quality issues that Mercedes never addressed. The parts and labor for this car are also expensive, and the car itself doesn't last long before the problems start. 

1 BMW E8x 1 Series

via: bmwblog.com

The 1 series hatchback was not sold in America. However, the coupe and convertible models were. As well as constant small electronic niggles, this car has some serious issues. Gasoline-powered cars have can experience loss of power which leads to engine vibrations and the car switching into "limp home" mode.

The worst model was the 135i, which was sold in the US. This takes all the original problems of the 1 series and ties them with the costly problems of the N54 engine seen in the e9x 335i. The 135i suffers from cracked turbos, leaks, and other costly issues and these cars are not cheap to repair.

NEXT: Steer Clear of These 10 American Muscle Cars