[vasillalov]

VANOS failures (not solenoid) would most probably result in poor lubrication due to overextending the oil drain interval usually combined with the use of fuel and/or oil additives. If there is sufficient lubrication there is absolutely no reason for the VANOS to fail (save for manufacturing defects which are rare). VANOS is purely mechanical.

[Keith_H1]

I bought a 2011 328i wagon from a used car lot a month ago and the "service engine" light came on as I was driving it home......no noises, just the "idiot" light. Since it only had 38,xxx miles and I had already verified (called BMW dealer with vin #) before buying it that it was still under the factory 4/50k warranty, I didn't worry about it. I set up an appointment with BMW/Nashville and they replaced a vanos solenoid. I drove it about 80 miles and the light came back on. I took it back yesterday morning and got a call near the end of the day that the vanos was going to have to be replaced. I'm not sure of the name of the specific component, but it appeared that it was a sprocket that had four bolts in it and three of them were backing out and causing the oil pressure operating the unit to fluctuate, which caused it to not work the valves properly. The only symptom I had was a 6 to 7 mpg reduction in fuel mileage.....which is significant. Anyhoo...... I have a 2014 528i loaner and should have one back sometime Monday. I had a 2007 Z4si coupe before this that had "zero" issues before I totaled it at 95,xxx miles so I hope this isn't something I've got to worry about after the warranty runs out. They said that keeping the oil changed is key to vanos longevity, and I'm an oil change fanatic (Mobil 1 European formula every 5k, or 7k if there's a trip to Houston, TX between changes) so I hope this is the end of the problem.

[Jklad]

Originally Posted by vasillalov

VANOS failures (not solenoid) would most probably result in poor lubrication due to overextending the oil drain interval usually combined with the use of fuel and/or oil additives. If there is sufficient lubrication there is absolutely no reason for the VANOS to fail (save for manufacturing defects which are rare). VANOS is purely mechanical.

This Probably also includes making sure the oil level is always topped off and never drops repeatedly to where an entire quart needs to be added back In.