[ats101]

Hi All,

I have planned a lovely road trip this weekend but unfortunately, my car has developed an issue yesterday.

I drive a 2009 325i coupe with the N53 engine. It has 104k miles on the clock.

My wife and I drove for about 4 miles to the park. About 30 mins later went to start the car again. It started fine. as soon as it reached idle revs, the car stalled in a slightly rough manner. There was a squeak from the engine bay that continued for 2 seconds a so after.

This happened 4 times. On the 5th, I gave it some gas, and the revs did not drop off and it did not stall. It drove back home ok, Its slightly rough on stopping at the lights but otherwise drove ok.

Today in the morning, it started fine and it did not stall, on first start up. I turned off the ignition and turned it back on and it did the stalling thing again.

We went out this afternoon and there is an intermittent squeak whilst driving - the squeak is there more often than not. Giving it some gas does encourage the squeak to go away. The stalling on starting it intermittent.

The noise is coming from driver the left of the engine when looking under the hood at the engine bay, towards the back. Please see videos.

It's not the alternator, it's not the belts. Maybe valvetrain related?

Any ideas.

TIA

[zerowaves]

This is going to sound really stupid but have you changed your oil recently? I did my first oil change on my E90 back in January and the oil filter cap has a piece that goes inside the filter. I didn't know this and threw it away by mistake, and about once a week I would get that same squealing noise and a rough idle. I replaced that missing piece from the filter cap and it hasn't happened since. I'm not sure how it's related, and it may not be the solution to your issue, but it would be worth taking a look. Good luck.

[ats101]

Hi,

Thanks fou your suggestion but I have not recently changed my oil.

Hmm anyone familiar with these symptoms?

[LanDzia]

Sounds like failing pcv. This one is integrated into valve cover, so whole valve cover required.
Research more PCV sound, sounds very similar!

Other thing that might sound similar is failed oil filter. Sometimes, especially when using cheaper brand oil filter, it collapses and creates such noise.
If you can, remove cap and inspect filter. It can be collapsed. In this case simply change to MANN and you're good to go.
Oh and while you're there check the cap if the seal is fine and cap not cracked anywhere. Can cause rough idle and maybe such sound?

[Mike K]

See if removing the oil fill cap changes the noise which could point to the PVC issue.

[ats101]

Thanks for the suggestion above.

Yes, taking the oil cap off took away the squeaking noise.

I have managed to get a Replacement PVC valve (after market) as these are bonded to the valve cover and I did not want to buy the whole valve cover.

I have managed to get the old one off by carefully prying it away was philips screwdriver and hammer.

When I put the new one on, does this have to be bonded on? If so, what do I bond it with that I could get from the hardware shop?

Thanks.

[ats101]

Update:

I did what I said I would. I broke the old one starting in the centre and then ripping off with pliers. Around the edge gentle taps flat head and hammer and cracked it away. It's does come apart. You cannot chip the plastic native to the valve cover.

There was a Large tear in the diaphragm.

And remaining plastic I sanded with course sand paper


I bonded with epoxy. I applied the epoxy around the to the valve cover rather than the replacement piece.


I have driving my car 150 miles and it has been sound. And actually - it is idling better than it has done in years.

I will post if it fails prematurely.

I hope this helps someone.