[chinna_n]

By recently bought 2007 - 328i with 94k miles, and it is making sound. More audible at idle outside the cabin. In cabin it is not bad. But I was wondering is this knocking? Or valve lash?

This is coming from passenger side of the engine bay, it seems like coming from below the valve train. But it might be possible it is coming from valve train.

Any ideas on what it is? and how to fix it?

[GoRomeo]

Vanos solenoids. Replace for new ones but before that, take them out clean them and swap them out. Easy job on our e90's

[chinna_n]

Just reading thru some other ticking noise threads. Is this similar to those ticking noise from oil starvation because of short drives?

But if you think it is Vano solenoids, is it ok to leave it alone with the sound? Does it cause any additional damage?

[ovaltine224]

Hey I've had that sound for a long time. I just figured it was normal lol

Thats not vanos solenoids, thats valve ticking theres a huge sticky thread about it.

[chinna_n]

After reading several threads, and seeing some videos, I finally can confirm it is not vanos solenoids. But it is air in HVA. Oil starvation due to short drives. I followed the bleed procedure and took it for a drive on highway for few miles.

Now, it is smooth, no more ticking.

I guess I need to take it on some highway trips weekly twice or thrice (like we take a doggy for walk ).

[Casca]

What is the bleeding process? Reading that 100+page thread, I have now read 30 post saying "........I did the bleeding process...." but nothing actually saying what it is. Feeling lazy, please make it easy

[chinna_n]

Here you go-- Google is your friend!

Very detailed explanation and procedure.
http://www.rtsauto.com/bmw-e90-valve...ter-ticknoise/

Anyways best things to do is, take the car for a 15-20min highway driving keeping the Engine RPM above 3000(I ran 4th gear Manual mode on highway so that oil pump builds enough pressure).

Ticking Noise SBSI B 11 09 07 -N52 Engine HVA System
________________________________________

This Service Information bulletin supersedes SI 11 09 07 dated April 2008.

designates changes to this revision

SUBJECT
Intermittent Hydraulic Valve Adjuster (HVA): “Ticking” or “Rattling” Noises

MODEL
All E82, E83, E85, E86, E88, E60, E61, E70, E90, E91, E92, and E93 with the N51, N52 or N52K engines

SITUATION
An occasional ticking or rattling noise from the HVA elements may occur during cold engine starts or frequent short-distance driving.

CAUSE
In these situations, the HVA elements may not yet have been supplied with sufficient amounts of air-free oil. This condition will not cause any damage to the engine, and usually remedies itself with a longer driving distance or operating times at full operating temperature.

CORRECTION
In the event of a customer complaint, please perform the following the HVA bleeding procedure.

PROCEDURE
Important notes:

The bleed time may take anywhere from between two minutes and (in rare cases) to a maximum of 30 minutes. This procedure is to be performed on a level surface with the vehicle stationary, and in a properly ventilated area.

Procedure preconditions:

Engine oil level correct – neither underfilled nor overfilled

Engine running at operating temperature

Bring the engine up to an operating speed (no load) of 2000-3000 rpm and maintain this condition for three minutes (bleeding procedure).

Let the engine idle for 15-30 seconds and reevaluate whether the noise is still present or not.

Engine quiet – procedure is finished.

Engine noise is still present – repeat the procedure; perform steps #1 and #2 up to a maximum of 5 times.

Only if the noise remains after performing the bleeding procedure 5 times: proceed by performing the procedure for a final time, also at an engine operating speed of 2000-3000 rpm, but for a total time duration of 15 minutes.

[Ph0zenstone]

How does this solve the problem? Seems it would just be a short fix but does not permanently fix the problem. As soon as you do some short drives it will come back again and you'd have to do the bleeding process again?

[chinna_n]

unfortunately that is true. Only fix is head replacement with new head which has a check valve.

It is design issue with BMW, but it seems they only fixed for people who complained under warranty.