Here’s a picture of a vacuum pump on a N54 and N55,,,we have noticed that he small vacuum fitting will start to pump some oil through the vacuum line,
This is the picture behind the vacuum port,,,inside is a small diaphragm that starts to break apart and starts to leak,,,letting oil getting pumped through the vacuum line.,,,,,the oil then gets pumped up to the turbo electro control boost valve that’s next to the valve cover,,,the one that sits by cylinders 4 and 5.,,,,you might see your electro control boost valve covered in oil,,,,that’s would be because of the oil getting pumped into it from the vacuum pump
bmwtechnician 
This is not normal, right? Does this cause the car to become low on oil eventually? Does this inhibit the turbo from operating properly, are there symptoms? Did the customer have a complaint? Just wondering.
-Oasis
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This is not normal,,,,we have only seen it twice so far,,,,will it cause low oil,,,,not really only over a very long time,,,,no it hasn’t effected the turbo
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The customer noticed a oil leak and smelled oil burning off the exhaust manifold
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Same questions here…
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Thanks for the replies. Good work.
-Oasis
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I noticed the vacuum hose from the solenoid soaked in oil. and oil leak near the solenoid. I traced the vacuum hose into the valve cover and notice that it had lots of oil inside. is this signs of a bad vacuum pump?
also is it normal for the valve cover to have no machined holes for 5 valve cover bolts? ive done lots of E series valve covers and know those with aluminum bolts had issues. but now to see a few bolts missing and not even machined into the valve cover and head is scary
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Yes this is a sign the vacuum pump is going bad,,,,,,ok on the valve cover not having screws by cylinder 5,,,,,,this is normal don’t worry about it.
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Hi,
How many hours labour is to change on a N55 F02?
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It should be about 3 hours
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are the rubber O rings seals on the n54 and n55 vacuum pump the same?
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I don’t know
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