W204 c300 oil smoke from exaust
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w204 c300
W204 c300 oil smoke from exaust
When i start car it start Smoke and stops after some sec so i have intake manifold problem its damaged and that can cause blue smoke from exaust or it should be pcv valve system. W204 c300 2008 m272 engine
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Joined: Oct 2016
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Mercedes C230 1997 W202
Hi, never fun with smoking tail pipes.
Milage on the engine?
What color of the smoke? Oil smoke is blueish and leaves residue. One way to test for oily smoke is putting a camera lens behind the tail pipe for a few seconds. If the image thereafter on the phone screen does not turn clear over a period of a few seconds, it is oil vapou stuck still on the lens and then oil vapour in the exhaust smoke.
A clogged or failed PCV system could cause smoke & oil consumption. It would do so as long as the engine is running. The vacuum / throttle will determine how much oil is sucked into the intake.
The common reason for oil on startup is worn valve stem seals. I have not read about it being a common failure point on these engines.
I just replaced my PCV M272 system in its entirety.
The most likely part causing an issue is the high pressure side PCV-valve. On left hand drive cars, it is located on the passenger side engine bank towards the firewall. Its membrane wears out causing oil to pass by. The second likely part causing an issue ia the hose having a narrow diameter passage as it enters the intake, so can clog up easily.
For a full PCV system replacement of the M272,
1 PCV valve passenger side (high pressure side)
1 PCV valve driver's side (low pressure side)
1 PCV oil collector, driver's side, directly behind the PCV valve (fitted with a reverse threaded screw)
1 long PCV hose from low prrssure side to intake
1 short PCV hose from high pressure side to intake
All screws are recommended to be replaced too.
Milage on the engine?
What color of the smoke? Oil smoke is blueish and leaves residue. One way to test for oily smoke is putting a camera lens behind the tail pipe for a few seconds. If the image thereafter on the phone screen does not turn clear over a period of a few seconds, it is oil vapou stuck still on the lens and then oil vapour in the exhaust smoke.
A clogged or failed PCV system could cause smoke & oil consumption. It would do so as long as the engine is running. The vacuum / throttle will determine how much oil is sucked into the intake.
The common reason for oil on startup is worn valve stem seals. I have not read about it being a common failure point on these engines.
I just replaced my PCV M272 system in its entirety.
The most likely part causing an issue is the high pressure side PCV-valve. On left hand drive cars, it is located on the passenger side engine bank towards the firewall. Its membrane wears out causing oil to pass by. The second likely part causing an issue ia the hose having a narrow diameter passage as it enters the intake, so can clog up easily.
For a full PCV system replacement of the M272,
1 PCV valve passenger side (high pressure side)
1 PCV valve driver's side (low pressure side)
1 PCV oil collector, driver's side, directly behind the PCV valve (fitted with a reverse threaded screw)
1 long PCV hose from low prrssure side to intake
1 short PCV hose from high pressure side to intake
All screws are recommended to be replaced too.
Last edited by Shadedmoon; Mar 13, 2025 at 05:18 PM.
