Planning a "mayor" tune-up

[Bmwtvboy]

bcbedliner is right. But keep in mind all that tear down and you may rebuild the top end intake. Don't change O2 unless you get code or other issue. Mine went 165K the first time around, second set still on at 241K. WHEN doing the intake manifold removal it's easier to get to all the vacuum lines and be sure to connect the small line going from the CCV to the oil pipe into the pan/block, this helps to improve vacuum pressure. If your doing all this front engine replacement, go ahead and do your Dvanos seals if they haven't been replaced. Good luck , have fun, these are easier and more roomy to work on than the E46 330 Ci.

[titodj]

Originally Posted by Bmwtvboy

Don't change O2 unless you get code or other issue.

If your doing all this front engine replacement, go ahead and do your Dvanos seals if they haven't been replaced.

Thank you... Two questions.
Why should I better wait until I get a code to replace the O2 Sensors?

On average at what mileage the Vanos has to be rebuilt?

Thanks !!