Cls 350 2012 oil leaks from breather hose
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Joined: Mar 2022
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Mercedes Cls350 2012
Cls 350 2012 oil leaks from breather hose
Days ago my car was dropping oil on the exhaust manifold from the breather hose and i had it fixed by the dealer.
surprisingly when it was leaking the car performance was actually very good responsive, powerful and very smooth when accelerating once it got fixed the car felt like chocked and losing power.
what can this be! Does it mean that the something might be cogged in the breather system?
Really need help!
surprisingly when it was leaking the car performance was actually very good responsive, powerful and very smooth when accelerating once it got fixed the car felt like chocked and losing power.
what can this be! Does it mean that the something might be cogged in the breather system?
Really need help!
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Joined: Apr 2008
Posts: 303
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2011 E550 (RIP), 2014 CLS 550C4
Ahmed, that hose probably connects to a PCV valve. The valve itself opens under certain conditions, usually when engine vacuum is high (like when decelerating or at idle) to allow crankcase fumes to be sucked out of the engine, but closes under low vacuum conditions (like when accelerating). It basically introduces a metered vacuum leak. If the valve isn't working properly, or if the wrong one was installed, it could create a constant vacuum leak, causing engine performance issues. Same thing with the hose itself, if it has any cracks or isn't clamped properly, you'll have a vacuum leak.
Thread Starter
Newbie
Joined: Mar 2022
Posts: 7
Likes: 0
Mercedes Cls350 2012
Ahmed, that hose probably connects to a PCV valve. The valve itself opens under certain conditions, usually when engine vacuum is high (like when decelerating or at idle) to allow crankcase fumes to be sucked out of the engine, but closes under low vacuum conditions (like when accelerating). It basically introduces a metered vacuum leak. If the valve isn't working properly, or if the wrong one was installed, it could create a constant vacuum leak, causing engine performance issues. Same thing with the hose itself, if it has any cracks or isn't clamped properly, you'll have a vacuum leak.
Is there any other breather hose in this engine? Does valve cover has a breather hose that connects with the pcv?
I assume that since the performance was good when the hose was leaking means that there is pressure inside the crankcase that is not vented correctly due to a clogged hose or something?
