[Malteser_wfj]

Hello everyone,

I'm new to this forum and to the E9x platform and N55 but not BMWs - I've had a 320i E30 and then two E46's, one 330ci manual and a 323i auto.

I bought this 2012 335i manual recently and it's developed a rather nasty noise.

It started out similar to this https://www.youtube.com/watch?v=EgU_yV3PYEE which made me think it was something to do with the AC system so I was going to get it check and topped up.

Then last night it started making it across a wider RPM range and louder too. The noise stops as soon as I release the throttle and starts again on the lightest application of the pedal.

I've compiled the videos I have into the youtube link below and will get some videos from the engine bay and at start up today before I drop the oil to inspect it for debris and pieces of metal.


BMW N55 knocking/fluttering sound (4) Static revving


BMW N55 knocking/fluttering sound (1)


BMW N55 knocking/fluttering sound (2)


BMW N55 knocking/fluttering sound (3)


What worries me is that it sounds almost identical to this... https://www.youtube.com/watch?v=ynzQuoTZ6LE


As you can see its got just shy of 120k miles


I will post pictures of the oil later today but any advice and experience is greatly appreciated!!

Thank you

[PhaceN52]

*cough

[Malteser_wfj]

Hahaha thanks, I've since realised and the oil did not look good!!

How do I upload my own photos?

[Malteser_wfj]

Okay think I figured it out.

Pictures of the oil and the particles collected by a paint strainer attached.

[PhaceN52]

Mmmh... do you diy? Without taking out the engine you could try to change the bearings, fill with a crappish oil and a new filter, turn the engine without the fuse on the fuel pump for trying to collect more bits of the old bearings, change oil again and go for it hopefully

[Malteser_wfj]

Originally Posted by PhaceN52

Mmmh... do you diy? Without taking out the engine you could try to change the bearings, fill with a crappish oil and a new filter, turn the engine without the fuse on the fuel pump for trying to collect more bits of the old bearings, change oil again and go for it hopefully

I do DIY but much smaller jobs like brakes, servicing and changing dampers etc. I don't have an engine stand or lift & with the weather we've got atm aren't too keen on getting on the ground currently!

I'm been speaking to a few different specialists about fitting a replacement engine as I think that will get me back on the road sooner. It's my only car so it being out of action for the near future isn't great.

[PhaceN52]

Yeah, you're right then, makes sense! Hope you'll be able to enjoy your car soon

[Malteser_wfj]

Thank you mate

[Malteser_wfj]

For anybody wondering there was a fully spun rod bearing