Bad noise from 2.0L engine when releasing quickly the throttle

[penant78]

Hi everyone,

I recently bought a 2005 Z4 with the 2.0L N46 engine. It only has 60000 miles.
It has a bad noise when I release quickly the throttle after a small acceleration.
It happens on standstill or when I'm driving, for example on acceleration at each gearchange.
Here is a short video of this.
https://youtu.be/eqnTvhzGgoU

I've tried to locate the noise and the loudest I hear it is in the back of the intake manifold.
Anyone already had the same noise?

Thanks, Franklin

 

[ph001]

Probably timing chain tensioner failed - the noise you can hear could be the timing chain hitting the cover?

 

[penant78]

That's what I thought after looking for answers on forums, but the noise is really coming from the back of the intake manifold

Probably timing chain tensioner failed - the noise you can hear could be the timing chain hitting the cover?

 

[ph001]

That's what I thought after looking for answers on forums, but the noise is really coming from the back of the intake manifold

Probably timing chain tensioner failed - the noise you can hear could be the timing chain hitting the cover?

On an M54 you would suspect the DISA valve but the N46 doesn't have the same setup... I've never heard of a problem in that area of the N46. I've heard of lots with timing tensioner failure though (and cracked exhaust manifolds).

 

[Kevoz4]

Hi Franklin, noises can be hard to track down. My Son’s VW Corrado VR6 had a similar noise and I was sure the noise was coming from the opposite side to the timing chain but it was the timing chain tensioner broken.

 

[Jfgoldfish]

Worth replacing the tensioner for the sake of preventative maintenance anyway. They are only about 45-50 quid from the dealer.
I did mine - it wasn't too worn.
Did one on a friends N46 and it could be compressed with light finger pressure!

If the tensioner is shot, it might be worth popping the valve cover off to check that the guides aren't broken.
It is quite an easy job to get it off and take a look. Just for piece of mind.

 

[Mike6]

I see people are advising the timing chain tensioner but dont discount the serpentine belt and its tensioner which would probably be due for renewal at that mileage.