[malgyver]

Hello all, thanks for any help in advance. I searched and didn't find much. 335i w/ 150K

I recently heard a new noise....its a light knocking at the front of the engine, hard to tell but it seems to emanate from the timing chain cover or right below the oil filter housing. The top black plastic motor cover is not installed, and hasn't been in a long time.

It sounds the same as when my PS pulley came loose, however, I checked that, and its tight.

Knocks at and off idle, below about 1500 rpm. Otherwise no performance issues.

Any guesses? Is this what VANOS problems sound like? I've never had a problem with those thus far.

I'm going to work on a video in a moment.

Thank you!

[feuer]

Look at the movements of the belt tensioner and if matches the knocking sound you found the cause.

[malgyver]

I jacked it up and got under it.

Its sounded like the PS Pulley, because it WAS the PS Pulley. One missing bolt and one loose. I guess a moot post. Moderators can delete I suppose.

When I visualized the top of the pulley, the runout looked about 1/16", so I didn't suspect it. The tensioner also had the slightest amount of movement, but not what I would have expected from that volume of knock..

[feuer]

Originally Posted by malgyver

I jacked it up and got under it.

Its sounded like the PS Pulley, because it WAS the PS Pulley. One missing bolt and one loose. I guess a moot post. Moderators can delete I suppose.

When I visualized the top of the pulley, the runout looked about 1/16", so I didn't suspect it. The tensioner also had the slightest amount of movement, but not what I would have expected from that volume of knock..

"It sounds the same as when my PS pulley came loose, however, I checked that, and its tight."

[malgyver]

Yes yes yes I know. In my first episode of this, the pulley was so loose I could move it with my hand even with the belt tension. So my first diagnostic procedure was to grab it and try to move it, and it was "tight".