Mercedes 2.2 CDI OM611 Engine Review, Specs, History, Problems, Reliability

Mercedes 2.2 CDI (OM611) Engine Specs, Problems, Reliability

Photo of author

By Scott Matthew

The inline 4-cylinder turbodiesel 2.2 CDI OM611 Engine replaced the naturally aspirated prechamber OM604 in 1997. The new engine was the first common rail Mercedes diesel engine. He made his debut on the C-class W202 in 1998. It was also installed on the E-class W210, Vito and Sprinter.

This engine continued the modular tradition. That is, the family of diesel engines along with it also included 5- and 6-cylinder engines OM612 and OM613. In fact, they differ only in the number of cylinders. Their pistons are exactly the same.

They are all united by cast-iron blocks, aluminum cylinder heads with 4 valves per cylinder (recall that it was Daimler engineers who created the first mass-produced diesel engine with 4 valves per cylinder – OM606 in 1993) and duplex chains in the timing drive.

The 2.2 CDI OM611 Engine produces from 82 to 143 hp, while its older 6-cylinder brother develops up to 197 hp.

Read Also: Toyota 4.0 1GR-FE V6 VVT-i Engine Problems And Reliability

Specifications Of The Mercedes 2.2 CDI OM611 Engine

Modification: OM611 DE 22 LA red. or 200 CDI

Exact Volume2151 / 2148 cm³
Supply systemCommon Rail
ICE power102 – 115 HP
Torque235 – 250 Nm
Cylinder blockcast iron R4
Block headaluminum 16v
Cylinder diameter88 mm
Stroke88.4 / 88.3 mm
Compression ratio18
ICE featuresintercooler
hydraulic liftersyes
Timing drivechain
Phase regulatorNo
Turbochargingyes
What oil to pour6.0 liters 5W-30
Fuel typeDiesel
Environmental classEURO 3/4
Sample resource450,000 km

Modification: OM611 DE 22 LA or 220 CDI

Exact Volume2151 / 2148 cm³
Supply systemCommon Rail
ICE power125 – 143 HP
Torque300 – 315 Nm
Cylinder blockcast iron R4
Block headaluminum 16v
Cylinder diameter88 mm
Stroke88.4 / 88.3 mm
Compression ratio18
ICE featuresintercooler
hydraulic liftersyes
Timing drivechain
Phase regulatorNo
Turbochargingyes
What oil to pour6.0 liters 5W-30
Fuel typeDiesel
Environmental classEURO 3/4
Sample resource400,000 km

2.2 CDI OM611 Engine Fuel Consumption

On the example of a 2002 Mercedes C220 CDI with a manual transmission:

City8.6 liters
track4.8 liters
Mixed6.2 liters

Which Cars Were Equipped With The O2.2 CDI OM611 Engine

Mercedes
C-Class W2021997 – 2001
C-Class W2032000 – 2003
C-Class CL 2032000 – 2004
E-Class W2101997 – 2002
V-Class W 6381999 – 2003
Sprinter W9012000 – 2006

2.2 CDI OM611 Engine Problems & Reliability

Mercedes diesel is very reliable and will easily pass even 1 million km. Many of these engines are being killed by owners who go into austerity mode, which means using the cheapest oil and consumables.

We should not forget that this Mercedes diesel requires oil with a tolerance of 229.1. This is not the coolest tolerance, but you should not neglect it.

Most 2.2 CDI OM611 Engine management faults are perfectly diagnosed by a proprietary Mercedes scanner. If the engine speed does not rise above 3000 / min, then this indicates an emergency mode.

Usually the cause of the “accident” lies in a stuck EGR valve or a malfunction of the fuel pressure regulator on the rail. Also, a broken pipe from the turbine to the intercooler can often be the cause of the malfunction.

1. Intake manifold

In the intake manifold of the 2.2 CDI OM611 Engine there are flaps for the filling channels. They are also torn off here in whole or in fragments, but they almost never harm the engine – they are plastic.

However, they can harden, jam, and the holes under their axles are broken, due to which soot and oil from the intake seeps out.

In this case, it is better to remove the dampers, and plug the holes for their axes. Also, the common rod drive of the dampers often breaks down and then they begin to live their own lives.

2. Fuel filter

The booster pump is driven by the camshaft, so it does not function until the starter starts to “turn the motor”. When replacing the fuel filter on the 2.2 CDI OM611 Engine, its housing must be filled with diesel fuel manually.

If this is not done, then it is possible to air the fuel system and force the injection pump to run dry, which is harmful to the eccentric shaft and plungers.

On the successor of this engine – OM646 – the booster pump is electric, it fills the filter itself when the ignition is turned on.

3. Bosch fuel system

So, after the Fiat’s 1.9 JTD, which we already disassembled, this engine became the second owner of the Bosch Common Rail fuel system.

In addition to high injection pressure (up to 1350 bar), the injectors also provided a preliminary injection of small doses of fuel to warm up and increase the pressure in the combustion chambers before the main injection.

Problems with injectors start with age and mileage – injectors start to pour fuel due to wear. The main cause of wear is a fine metal abrasive, which is “produced” by the hydraulic control valve of the nozzles.

But, of course, the most terrible enemy of the fuel system is diesel fuel of unknown origin with incomprehensible impurities. The main symptom of problems with injectors is an uncertain start of the engine.

Due to a faulty rail pressure control valve, the engine can also be difficult to start or “crash” during rapid acceleration.

4. Nozzle washers

Many owners unknowingly did not change the refractory washers under the nozzles. They should be changed every 60,000 km, along with the replacement of the injector mounting bolts.

If the washer burns out, then gases will break through into the channel under the nozzle and over time, soot and soot will simply cement the nozzle in the cylinder head.

Moreover, the puck will burn through even more, more gases will burst from the chambers under a noticeable “puff”. Treatment of the “forgetfulness” of the owner will cost at least $ 50. for pulling out one injector.

5. Glow plugs

Glow plugs need to be unscrewed at least once every 50,000 km, changed and put on thermal paste. Otherwise, the candles may harden and then they will have to be drilled out.

6. Injection pump

The first generation Bosch CP1 fuel pump is also very reliable. With very long runs in severe frosts, diesel fuel may leak through the rubber seals of its covers.

They are all sold as a single kit. Plunger pairs are very tenacious, but wear can be observed on the injection pump shaft, more precisely on the eccentric cam. The shaft can be changed separately.

7. Turbine

The first versions of the 2.2 CDI OM611 Engine were equipped with a wastegate turbocharger. Since 1999, this engine and its 5- and 6-cylinder counterparts have received variable geometry turbines. All engines are equipped with intercoolers.

8. Crankshaft

The crankshaft of the 2.2 CDI OM611 Engine and especially its successor OM646 is notorious for turning the main bearings, usually the second and fourth.

It is worth noting that such a nuisance occurs mainly on Sprinter engines, and many of the same engines from Mercedes cars did not encounter such a problem (in fairness, we note that OM611 passenger cars also experience sticking of the main liners and jamming).

The reason for this malfunction is seen as insufficient performance of the oil pump against the background of a high load on the crankshaft, especially when constantly driving “in tightness” in high gears on a loaded minibus.

In the most severe cases, the crankshaft cracks. Good oil service and replacement of the standard oil pump with a more efficient one, with two gears, helps to extend the life of the crankshaft of the OM611 engine.

Conclusion

The 2.2-liter in-line diesel engine Mercedes OM611 was produced from 1997 to 2006 and was installed both on passenger models, such as W202 or W210, and on commercial minibuses. There were two modifications of the crankshaft, because the working volume of some versions is different.

Leave a Comment