Thinking of getting E53 4.4 or 4.6

[stiubhartach]

Originally Posted by killcrap

Unfortunately this is false. The N62 has easy to service vent valves and it will be very obvious when there is an issue with them. Usually service engine soon with mixture faults or checksum faults.
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I disagree. When I had my smoking issues, I didn’t have any engine faults. And the vent valves, while easy to service, sit on top of an oil maze in the valve cover than needs to be cleaned and rarely is.

I bought my X5 from the original owner for a steal because it was occasionally smoking and the dealer told him it needed valve stem seals. The dealer had serviced the CCV system, but failed to clean the valve covers correctly which prevented the valves from closing under high intake manifold vacuum. This allowed oil to be sucked into the intake manifold and eventually into the cylinder.

I pulled the valve covers and cleaned them correctly, installed new vent valves and the problem went away for several years. Until it was time to replace them again.

It’s easy enough to check for oil in the intake manifold with a boroscope. This is positive proof oil CCV failure. If the intake manifold is dry, then it most likely is valve stem seal. I theorize that many of early valve stem seal failure diagnosis are actually just CCV failure.


Here’s a write up I did:

https://xoutpost.com/bmw-sav-forums/...lem-fixed.html