Mercedes-Benz M119 Engine Problems – Greatest V8 Ever?

Featured image: HLW1993 MB 500 SL R 129 Motor 1092CC BY-SA 3.0

Just about any Mercedes-Benz enthusiast out there will agree that the 90s were the golden years of Mercedes-Benz. During that time, they built some of the most over-engineered cars and engines in the world. Not only did they make some of their most renowned models like the W124 or the R129 SL, they also built some of the most reliable engines ever, and the M117 is one of them.

💡 This legendary V8 is a successor to the already incredible 80s M117 V8 engine and like our title suggest, you should buy one right now if you’re lucky enough to find it in good condition.

The M119 engine featured a 90 degree V8 configuration in a 4.2, 5.0 or the 6.2 L displacement. Double overhead cam design featured 4 valves per cylinder with variable valve timing. Unlike the M117 engine, the M119 featured an aluminium cylinder head, forged con rods that allow for cooling of the pistons with sprayed oil and pistons made out of iron coated cast aluminium.

The M119 was also much smoother with improved vibration damping system and an improved intake camshaft timing that allows for improved idle and increased torque.

Enough theory, let’s dive into the these mercedes engine problems (there’s not a lot tbh)!

Common Mercedes-Benz M119 Engine Problems

If you’re running low on time, we got your back.

Here are all the common Mercedes-Benz M119 engine problems:

  • Timing chain guides
  • Exhaust lifter knock & plastic oil guides
  • Timing chain & timing chain tensioner inspection
  • Hardened vacuum lines
  • Power steering pump hose leaks
  • Engine wiring harness
  • Plastic oiler tubes, cam oilers
  • Purge canister valve

It’s worth noting that the majority of these issues can be fixed with very little investment, and some of them can even be prevented with regular maintenance and care. Now let’s dig a little deeper into each of those common Mercedes gas engine problems.

Engine wiring harness

Let’s start with what is essentially the only serious common problem of the M199 engine. With no surprise at all, it’s the engine wiring harness.

An engine wiring harness is a bundle of cables, wires, and connectors that controls the vehicle’s electrical system. 

The wiring harness is responsible for conveying the information from the engine control unit to the fuel injection system, the alternator, the battery and so on.

The M119 engine is known for running hot, especially in vehicles where there is less wiggle room around the engine (the W124, the R129 SL). The heat eventually destroyed the wiring harness, resulting in various engine issues or erratic behaviour. But heat is not the only thing responsible for these issues.

The 1993 and later model year M199 engines came with wiring harnesses made out of biodegradable material, which was more prone to degradation and eventual failure. Replacing the harness requires a knowledgable mechanic, few hours of labour and approx $500 in parts.

Timing chain guides

Certain model years of the M119 engine came equipped with plastic timing chain guides. Timing chain guides act as a track upon which the timing chain connects the crankshaft and the camshafts.

The plastic track guides were prone to breaking down due to age and heat, so they must be inspected and replaced preventively. They cost less than $20 but act as a crucial component that can lead to catastrophic engine damage if they fail.

These plastic timing chain guides are easily accessible under the valve cover. Any good mechanic will inspect this guides when inspecting the timing guide. Certain cars like the 1992 W124 500E came with metal timing chain guides which were more durable.

Exhaust lifter knock & plastic oil guides (cam oilers)

Another issue that is easily resolved at the same time as the timing chain guides is the plastic oil guides that supply oil below to the bottom exhaust lifters. The oil guides should deliver a tiny amount of oil beneath the lifters where the valve stem hits.

This $300 DIY repair will forever resolve the annoying lifter knocking sound that many owners tend to ignore for years. If you want the whole story of this problem, see this amazing visual Oil guide DIY process by Greg Baxter.

Timing chain & timing chain tensioner inspection

There’s a small group of owners that would claim that the M119 engine suffers from timing chain stretching problems. We’d have to strongly disagree.

While it is normal that the timing chain does start knocking at 200,000 miles (ca. 321,869 km) and more, we wouldn’t exactly call this a common concern, especially not at those mileages.

This problem is more common on vehicles that were poorly maintained and driven hard before warming up.

Mercedes recommends inspecting the timing chain regularly, however not a lot of owners decide to replace it before the car reaches extremely high mileages. When the timing chain becomes stretched, it releases the typical knocking sound that last 2–4 seconds on a cold startup.

Hardened vacuum lines

The last M119 engine was built more than 20 years ago at this point. If you’re in the market for a M119 powered Benz today, be ready to have fun with all kinds of hardened plastic tubes. It’s completely normal for plastic and rubber to harden and become brittle.

Unless you’re buying a well maintained car, you can expect to replace a number of plastic tubes and rubber gaskets.

Power steering pump hose leaks

We’re adding the power steering pump hose leaks to the list of numerous rubber hoses that eventually deteriorate to the point where they start leaking.

Keep a close eye on the steering fluid level and take action as soon as it starts suspiciously disappearing.

Purge canister valve

This is a funny one, the truth is 99% of owners don’t even realize that their purge canister isn’t working properly. When it does work properly, the fuel tank vapours get caught in a charcoal canister. With the help from a regeneration valve, the contents of the said canister get sucked into the intake manifold, where they get burned.

When it works properly, the purge canister makes a distinct clicking sounds. This system represent early attempts at emission controls. The majority of the cars will run just fine with a dead purge canister valve, however, it did result in poor idling in a few vehicles.

M119 Engine Variants and Applications

The table below shows all the variants of the M119 engine and the vehicles that were equipped with a particular variant.

Fun fact: The legendary 1998 Mercedes-Benz CLK LM came with a naturally aspirated V8 M119 engine. The Sauber C9 racing car and the Mercedes-Benz C11 came with a bi-turbo M119 E50 engine!

Engine VersionBasic SpecificationsCars with this engine
M119 E424.2L / 268–282 horsepowerW124 – 400E / 420E / 4.2 AMG
W210 E-Class E420
W140 S-Class 400 SE(L) / S420
C140 CL420
M119 E505.0 L / 315–342 horsepowerW124 500E
W140 S-Class S500
C140 CL500
R129 SL500
W210 E-Class E50 AMG
CLK LM
M119 E606.0 L / 369–375 horsepowerW124 E60 AMG
W210 E-Class E60 AMG
R129 SL60 AMG

Conclusion

It’s no wonder why the M119 engine boasts an almost cult following amongst Mercedes-Benz fans. This legendary V8 will go down in history as one of the greatest engines of the 90s or perhaps, ever.

If you can find a car with this engine with a clear maintenance history, you should not hesitate one bit to buy it. After all, regular maintenance is really all these engines ever need. Numerous owners who passed incredible mileage milestones with these engines would swear by that fact, the M119 is just so good.

FAQ

Which Mercedes models had the M199 Engine?

The M119 engine was found in several Mercedes models, including:

  • W124 500E
  • W124 400E
  • W124 E60 AMG
  • W210 E60 AMG
  • W140 S500
  • W140 S400/420
  • C140 CL500
  • R129 SL500
  • R129 SL60 AMG
  • W210 E420
  • W210 E50 AMG

Is the Mercedes M119 engine reliable?

Yes, in fact, it’s one of the most reliable Mercedes engine ever. Based on our experience and the experience of numerous owners, this engine will easily last 300,000 miles (ca. 482,803 km) and more with just regular maintenance and care.

Mercedes M119 vs M113, which is better?

We would have to say that the M119 was still a better engineered and more reliable option. However, it is worth mentioning that the M113 is both more advanced and powerful, which means it is slightly more prone to oil leaks and other issues. Nevertheless, the M113 is an extremely reliable engine, you can read our full M113 engine review to learn more.

About The Author

1 thought on “Mercedes-Benz M119 Engine Problems – Greatest V8 Ever?”

Comments are closed.