# Oil leak at exhaust cooler



## montr (Oct 7, 2006)

I have an oil leak (or soot leak) at the hose circled in red. Anyone knows what is this hose? Any O-ring to replace?

Edit: In page 79 of ST810, it show the hose is for the coolant. It appears that my leak is not from the coolant hose coupler but it is from high pressure EGR valve shaft. Anyone with same problem?

Thanks


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## imtjm (Oct 5, 2004)

montr said:


> I have an oil leak (or soot leak) at the hose circled in red. Anyone knows what is this hose? Any O-ring to replace?
> 
> Edit: In page 79 of ST810, it show the hose is for the coolant. It appears that my leak is not from the coolant hose coupler but it is from high pressure EGR valve shaft. Anyone with same problem?
> 
> Thanks


Did you figure it out? A common problem is the Charge Air Line (11617812274), oil leak around the seals. http://www.bimmerfest.com/forums/showthread.php?t=753755
The link shows an after market replacement, but you get the drift. You can see it on the left side of between the engine and the fan by the bottom right of the mass air filter housing (look low). You should see a large wide red rubber hose, which may be all oiled up.

If that is the problem, you also might find your turbo oil pipes (three of them) leaky, too. Seems more than a few people noticed leaks of the turbo oil pipes when replacing the Charge Air Line. The turbo oil pipe parts 11427795972, 11427795970, 11427795971)


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## montr (Oct 7, 2006)

imtjm said:


> Did you figure it out? A common problem is the Charge Air Line (11617812274), oil leak around the seals. http://www.bimmerfest.com/forums/showthread.php?t=753755
> The link shows an after market replacement, but you get the drift. You can see it on the left side of between the engine and the fan by the bottom right of the mass air filter housing (look low). You should see a large wide red rubber hose, which may be all oiled up.
> 
> If that is the problem, you also might find your turbo oil pipes (three of them) leaky, too. Seems more than a few people noticed leaks of the turbo oil pipes when replacing the Charge Air Line. The turbo oil pipe parts 11427795972, 11427795970, 11427795971)


Yes. The problem is a crack in the weld between the square to the oval section. It is just above the area that I circled in RED. Also, the return spring to the exhaust valve (inside the EGR cooler) is broken. This is why I am getting the following fault:
Fault code 4873 (OBD code P2457) Additional EGR cooling, plausibility: Additional EGR cooler bypass valve does not open

I had to remove the EGR cooler from the car to find out. I am waiting for a new EGR cooler, it should arrive this weekend.

Here is the diagnostic for fault code 4873:
Fault code 
4873 - P2457

Fault text 
Exhaust gas recirculation cooling, plausibility:

Fault description 
Monitoring EGR cooler bypass valve. 
The temperature downstream from the EGR cooler bypass valve is stored at specific times. 
The stored temperatures are employed to generate two temperature gradients. 
An activation signal is transmitted to the EGR cooler bypass 
valve while the temperature gradients are being generated. If 
the EGR cooler bypass valve is in good condition then a 
temperature variation must be apparent. In contrast, if the 
EGR cooler bypass valve is defective then virtually no 
variation in the temperature gradient will be apparent. 
The diagnostic trouble code is logged when the absolute 
difference between the temperature gradients falls below the 
limit value 5 K.

Condition for fault identification 
Test condition:
The check runs every 100 ms when all of the enable conditions are present: 
- For a duration of 1000 ms the specified torque gradient is below 4 Nm/s. 
- The rpm is within the limits 980 1/min and 590 1/min. 
- For the duration 1000 ms the modeled exhaust-gas recirculation rate is greater than 21. 
- The engine is running at idle. 
- The air mass control/EGR rate control is active and no deactivation conditions are active. 
- The vehicle speed is less than 3 km/h. 
- The engine is not in the regeneration mode. 
- The coolant temperature is between 60 ?C and 110 ?C. 
- The modeled exhaust-gas temperature is greater than EGRClg_tExhMnfUsThresLo_C. 
- The temperature behind the EGR cooler is below the limit value 1 K/s. 
- The injection rate is between 6 mg/hub and 100 mg/hub. 
Voltage condition: 
The check runs every 100 ms when all of the enable conditions are present: 
- For a duration of 1000 ms the specified torque gradient is below 4 Nm/s. 
- The rpm is within the limits 980 1/min and 590 1/min. 
- For the duration 1000 ms the modeled exhaust-gas recirculation rate is greater than 21. 
- The engine is running at idle. 
- The air mass control/EGR rate control is active and no deactivation conditions are active. 
- The vehicle speed is less than 3 km/h. 
- The engine is not in the regeneration mode. 
- The coolant temperature is between 60 ?C and 110 ?C. 
- The modeled exhaust-gas temperature is greater than EGRClg_tExhMnfUsThresLo_C. 
- The temperature behind the EGR cooler is below the limit value 1 K/s. 
- The injection rate is between 6 mg/hub and 100 mg/hub.

Condition for fault memory entry 
-

Action in service 
Check vacuum supply to the EGR cooler's bypass valve (vacuum lines and switch valve).
If the vacuum supply is in satisfactory condition: *Replace the EGR cooler (the bypass valve's return spring
may be defective). *

Fault effect and breakdown warning 
Proceed to the nearest BMW Service facility.

Driver information 
Warning light: 
MIL

Service instruction 
none


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## Doug Huffman (Apr 25, 2015)

What is your source of the fault text, please?


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## ninja_zx11 (Feb 13, 2014)

Doug Huffman said:


> What is your source of the fault text, please?


Its from Rheingold or ISTA/D (BMW factory diagnostic software).


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## imtjm (Oct 5, 2004)

so what's the oil leak?


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## montr (Oct 7, 2006)

It is an exhaust soot leak.


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