E200 CDI W212 Ticking noise OM651
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Mercedes E200CDI W212
E200 CDI W212 Ticking noise OM651
Hello guys, I have a Mercedes E-Class 200 CDI W212 with the OM651 engine. Recently the engine started knocking — the sound comes from the upper part of the engine. The knocking is present both when the engine is cold and when it is warm. When I give it gas, the knocking sound becomes less noticeable, but the frequency increases with RPM. Additionally, the car produces black smoke, loses power under load, and does not rev over 3000 RPM. I recently changed the engine oil and oil filter, but the problem remains. What could be the cause? Thanks in advance for your help!
Last edited by Petrovv; Apr 27, 2025 at 10:03 AM.
Out Of Control!!
Joined: Apr 2019
Posts: 11,924
Likes: 6,776
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
WEAK OM651 DIESEL
Engine does sound really weak.
How old is the FUEL FILTER???
Check your cylinder compressions: not yet!
How many total Miles/Km?
What chassis codes are you getting?
Injection timings is 100% on ECU work.
What different oil grade and filter has this engine had ??
How often replaced?
How old is the FUEL FILTER???
How many total Miles/Km?
What chassis codes are you getting?
Injection timings is 100% on ECU work.
What different oil grade and filter has this engine had ??
How often replaced?
Last edited by CaliBenzDriver; Apr 27, 2025 at 01:46 PM.
Thread Starter
Newbie
Joined: Apr 2025
Posts: 11
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Mercedes E200CDI W212
Engine does sound really weak.
How old is the FUEL FILTER???
Check your cylinder compressions: not yet!
How many total Miles/Km?
What chassis codes are you getting?
Injection timings is 100% on ECU work.
What different oil grade and filter has this engine had ??
How often replaced?
How old is the FUEL FILTER???
How many total Miles/Km?
What chassis codes are you getting?
Injection timings is 100% on ECU work.
What different oil grade and filter has this engine had ??
How often replaced?
- The fuel filter is around 15,000 kilometers old.
- The car has 260,000 kilometers.
- There are no errors on the computer.
- The injectors are functioning properly.
- I use 5W-30 engine oil and a Mann filter.
- I've had the car for 3 years and have driven 30,000 kilometers; I just changed the oil for the second time.
Last edited by Petrovv; Apr 27, 2025 at 02:13 PM.
Out Of Control!!
Joined: Apr 2019
Posts: 11,924
Likes: 6,776
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
- The fuel filter is around 15,000 kilometers old.
- The car has 260,000 kilometers.
- There are no errors on the computer.
- The injectors are functioning properly.
- I use 5W-30 engine oil and a Mann filter.
- I've had the car for 3 years and have driven 30,000 kilometers; I just changed the oil for the second time.
then onto cylinder ompression checks.
Thread Starter
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Joined: Apr 2025
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Mercedes E200CDI W212
Here is a slightly better explanation of the situation regarding my car
First, the car started losing power uphill, or when the gas pedal was pressed suddenly (RPM). I put it on diagnostics and these errors came up:
P0087 Fuel Pressure: Value below threshold
P0426 Catalyst Temperature Sensor 1
P2080 Exhaust System Temperature Sensor 1
P0252 Quantity Control Valve Output has an electrical faultNow, this is happening: the engine started knocking from the top, and the knocking is the same whether the engine is cold or warm. As the RPMs increase, the knocking intensifies but the sound decreases.
The injectors have been checked – they are fine.
I changed the oil and filter.
In the old oil filter, there were no metal shavings.
What could be the cause of this problem?
The car has 260,000 km.
I’ve owned it for 3 years (30,000 km driven).
It has had 2 minor services (oil + filters).
Now, after the knocking started, I immediately changed the oil.
First, the car started losing power uphill, or when the gas pedal was pressed suddenly (RPM). I put it on diagnostics and these errors came up:
P0087 Fuel Pressure: Value below threshold
P0426 Catalyst Temperature Sensor 1
P2080 Exhaust System Temperature Sensor 1
P0252 Quantity Control Valve Output has an electrical faultNow, this is happening: the engine started knocking from the top, and the knocking is the same whether the engine is cold or warm. As the RPMs increase, the knocking intensifies but the sound decreases.
The injectors have been checked – they are fine.
I changed the oil and filter.
In the old oil filter, there were no metal shavings.
What could be the cause of this problem?
The car has 260,000 km.
I’ve owned it for 3 years (30,000 km driven).
It has had 2 minor services (oil + filters).
Now, after the knocking started, I immediately changed the oil.
Out Of Control!!
Joined: Apr 2019
Posts: 11,924
Likes: 6,776
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Here is a slightly better explanation of the situation regarding my car
First, the car started losing power uphill, or when the gas pedal was pressed suddenly (RPM). I put it on diagnostics and these errors came up:
P0087 Fuel Pressure: Value below threshold
P0426 Catalyst Temperature Sensor 1
P2080 Exhaust System Temperature Sensor 1
P0252 Quantity Control Valve Output has an electrical faultNow, this is happening: the engine started knocking from the top, and the knocking is the same whether the engine is cold or warm. As the RPMs increase, the knocking intensifies but the sound decreases.
The injectors have been checked – they are fine.
I changed the oil and filter.
In the old oil filter, there were no metal shavings.
What could be the cause of this problem?
The car has 260,000 km.
I’ve owned it for 3 years (30,000 km driven).
It has had 2 minor services (oil + filters).
Now, after the knocking started, I immediately changed the oil.
First, the car started losing power uphill, or when the gas pedal was pressed suddenly (RPM). I put it on diagnostics and these errors came up:
P0087 Fuel Pressure: Value below threshold
P0426 Catalyst Temperature Sensor 1
P2080 Exhaust System Temperature Sensor 1
P0252 Quantity Control Valve Output has an electrical faultNow, this is happening: the engine started knocking from the top, and the knocking is the same whether the engine is cold or warm. As the RPMs increase, the knocking intensifies but the sound decreases.
The injectors have been checked – they are fine.
I changed the oil and filter.
In the old oil filter, there were no metal shavings.
What could be the cause of this problem?
The car has 260,000 km.
I’ve owned it for 3 years (30,000 km driven).
It has had 2 minor services (oil + filters).
Now, after the knocking started, I immediately changed the oil.
Because it's likely fuel, its less likely mechanical... that's a better chance to fix without engine swap.
Right now these faults are not active because the engine is right outside near that condition... yet it is the same issue you're dealing with.
P0087 Fuel Pressure: Value below threshold
P0252 Quantity Control Valve Output has an electrical fault
The bottom line is low fuel pressure... why?
Your filter is new already!
Read pressures with scanner.
suspect HPFP being original...
Does pressure collapse under load??
Last edited by CaliBenzDriver; Apr 27, 2025 at 03:56 PM.
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MBWorld Fanatic!
Joined: Oct 2010
Posts: 5,141
Likes: 1,293
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
Hello guys, I have a Mercedes E-Class 200 CDI W212 with the OM651 engine. Recently the engine started knocking — the sound comes from the upper part of the engine. The knocking is present both when the engine is cold and when it is warm. When I give it gas, the knocking sound becomes less noticeable, but the frequency increases with RPM. Additionally, the car produces black smoke, loses power under load, and does not rev over 3000 RPM. I recently changed the engine oil and oil filter, but the problem remains. What could be the cause? Thanks in advance for your help!
I have the DI m278 and it has two high pressure fuel pumps that are driven by the cam shafts, and I had noise coming from the fuel pumps that sounded similar to yours. Noise was strongest in the top back corner on passenger side where the pumps are located.
Without further diagnosis I replaced both pumps and lifters.
If the diesel fuel pump is driven the same way I would look into that first as all symptoms point to fuel delivery issue. This type of a pump has spring returned piston and when this spring dies the piston will not come back all the way after pumping stroke and so does not deliver full portion of the fuel. Noise comes from the cam follower losing contact with the cam and then hitting the cam next time it comes to do the pumping stroke.
New filter means there should not be issues before the fuel pump unless it there another transfer pump in the fuel tank like DI gasoline engines have.
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Thread Starter
Newbie
Joined: Apr 2025
Posts: 11
Likes: 0
Mercedes E200CDI W212
Yours is a diesel. How is the fuel pump driven on these engines?
I have the DI m278 and it has two high pressure fuel pumps that are driven by the cam shafts, and I had noise coming from the fuel pumps that sounded similar to yours. Noise was strongest in the top back corner on passenger side where the pumps are located.
Without further diagnosis I replaced both pumps and lifters.
If the diesel fuel pump is driven the same way I would look into that first as all symptoms point to fuel delivery issue. This type of a pump has spring returned piston and when this spring dies the piston will not come back all the way after pumping stroke and so does not deliver full portion of the fuel. Noise comes from the cam follower losing contact with the cam and then hitting the cam next time it comes to do the pumping stroke.
New filter means there should not be issues before the fuel pump unless it there another transfer pump in the fuel tank like DI gasoline engines have.
I have the DI m278 and it has two high pressure fuel pumps that are driven by the cam shafts, and I had noise coming from the fuel pumps that sounded similar to yours. Noise was strongest in the top back corner on passenger side where the pumps are located.
Without further diagnosis I replaced both pumps and lifters.
If the diesel fuel pump is driven the same way I would look into that first as all symptoms point to fuel delivery issue. This type of a pump has spring returned piston and when this spring dies the piston will not come back all the way after pumping stroke and so does not deliver full portion of the fuel. Noise comes from the cam follower losing contact with the cam and then hitting the cam next time it comes to do the pumping stroke.
New filter means there should not be issues before the fuel pump unless it there another transfer pump in the fuel tank like DI gasoline engines have.
MBWorld Fanatic!
Joined: Oct 2010
Posts: 5,141
Likes: 1,293
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
When I turn the ignition on, I can hear a loud bubbling/gurgling sound coming from the fuel pump located in the fuel tank (I'm not sure if this is normal).In the OM651 diesel engine of the Mercedes E-Class W212 200 CDI, there is only one high-pressure fuel pump, and it is driven by the camshaft (more precisely, by a separate camshaft eccentric) if im not wrong..
But the other problem can be, as I mentioned, the high pressure fuel pump spring losing force so the pump piston does not make the full stroke with cam follower losing contact with the cam lobes creating the noise when cam lobe hits it again and losing power/speed as there simply is not enough fuel in the cylinders.
Last edited by Arrie; Apr 27, 2025 at 05:58 PM.
