[RichardGoller]

I'm about to pull the valve cover on my N52 as I suspect there is something wrong with the top end of the engine and I'm thinking either a VANOS adjuster failed or the chain is worn. Obviously I'll know if it's the VANOS but what am I looking for on the chain, other than a loose chain? Should I turn the engine around and have a look around the chain? What am I looking for?

[E92William]

What are your symptoms or issues? Very rare to have chain problems on this engine

[RichardGoller]

Originally Posted by E92William

What are your symptoms or issues? Very rare to have chain problems on this engine

Low and rough idle when AC is off, around 550 rpm and a sort of vibration, more like rumbling that sakes the whole car at intervals that don't really have a rythm, it's not like it's related to rpm. Also when this rumbles occur and you hold your hand to the exhaust you can feel the pulse. And when you open the bonnet and listen carefully there is a noise coming from the top of the engine, if I had to say what it sound like to me it's like metal rubbing on plastic. Again this only happens at idle when AC is off, other wise it feels fairly smooth. Changed the vanos solenoids to genuine BMW, I had the big DISA fail, replaced that, but the problem is still there. I'm getting a code for oil pressure swith plausability but I'm not sure if thats related and that is the only fault code I have.

[lowrydr310]

Originally Posted by RichardGoller

Low and rough idle when AC is off, around 550 rpm and a sort of vibration, more like rumbling that sakes the whole car at intervals that don't really have a rythm, it's not like it's related to rpm. Also when this rumbles occur and you hold your hand to the exhaust you can feel the pulse.

Sounds like the symptoms I had when my engine mounts were collapsed. Not saying that's the issue but worth checking out.

[RichardGoller]

Originally Posted by lowrydr310

Sounds like the symptoms I had when my engine mounts were collapsed. Not saying that's the issue but worth checking out.

I want to replace those too, but I want to make sure that if it's an issue that needs to be sorted I sort it, instead of putting on new engine mounts so that I can't feel it

[Dru128m]

Maybe a small leak in the intake beyond the MAF causing some lean misfires at low idle. Maybe a coil going bad. Can't see much chain with the valve cover off, kind of a pain to pull and reinstall if that's not it. Chain tensioner is easy to do if nothing else comes up. The whole timing chain is always rubbing against plastic so hard to say, but known to be quite reliable. My money goes on coils. Good luck.

[RichardGoller]

Originally Posted by Dru128m

Maybe a small leak in the intake beyond the MAF causing some lean misfires at low idle. Maybe a coil going bad. Can't see much chain with the valve cover off, kind of a pain to pull and reinstall if that's not it. Chain tensioner is easy to do if nothing else comes up. The whole timing chain is always rubbing against plastic so hard to say, but known to be quite reliable. My money goes on coils. Good luck.

Thanks. Pulled the cover, can't see anything wrong with the chain or VANOS, I'm thinking the same, sprark plugs were changes about a year ago, so will do coils. Eccentric shaft sensor seems to have a bit of oil, but I will first try other things before that, since It shows no codes. Will try to do a software update aswell

[Nhlapoth]

Myn does have the s5ane symptoms but its happening frequently now. Sonetime it start idling well but aftrr reving engine or when driving it start ra kling the engine and even stalling. And the error code say something about vanos referencing.