Vibration at very low rpm after oil change - BMW e90

blun · 13 Nov 2011 at 13:08

No warranty - just £1k per year in the emergency fund. 100k+ miles so warranty is a non starter.

Thanks for the advice pepsilol, will check that out.

pepsilol · 13 Nov 2011 at 17:03

My N52 is idling at 600, 500 does sound too low. It really does sound like your adaptions are out.

Also reset your throttle while you're at it.

And obviously check your error codes to see if anything is there.

pepsilol · 13 Nov 2011 at 20:14

Just thought of something probably stupid and crazy....

Could having the car running on 5w30 all off its life and then suddenly changing to 0w40 have an affect? Kind of ties in with adaptions being used to the thinner oil and now having a thicker one?

Out of the box and most likely stupid but maybe?

blun · 13 Nov 2011 at 21:57

The car should have been running 0w30 anyway I think - however I don't think there's any way to know for sure.

pepsilol · 13 Nov 2011 at 23:30

I was under the impression castrol 5w-30 was always used on our cars...

blun · 14 Nov 2011 at 08:27

The more I read, the more I think it probably was running 5w30 before. Will having changed to 0w30 caused this problem? Will just driving the car for a few weeks allow it to adapt to the new oil?

I normally do a lot of short journeys, so am I right in thinking that 0w30 oil will protect the engine from cold better than 5w30 ? (sorry if I sound completely dense - I'm not clued up on how different oil grades work)

[TW]Fox · 14 Nov 2011 at 08:46

It's vibrating at 500rpm because you are not supposed to run the engine at 500rpm not because of the oil your dealer correctly filled it with!

pepsilol · 14 Nov 2011 at 09:25

I thought it was idling at 500 in neutral?

blun · 14 Nov 2011 at 09:50

Thats right - With the a/c and lights turned off it idles at 500rpm in neutral. It's done this for the last 2 years and it's never been a problem.

Then, if you raise the revs very slowly, there's a really obvious vibration / rattle at around 600 rpm, which then goes away at 700+ rpm.

[TW]Fox · 14 Nov 2011 at 10:18

The idle is not right. I suspect its related to your problem.

blun · 16 Nov 2011 at 19:57

Quick update for anyone thats interested:

Took the car to BMW and they gave it a good check over. Couldn't find anything relating to the oil change that would be causing the problem. I asked abou the idle speed and they said it was fine (it's about 550rpm with everything switched off, 600ish with the AC on). Checked the OBD for faults and all clear.

The technician said the noise isn't coming from the engine itself but wasn't up for doing any further diagnosis without me getting my wallet out.

So.. I think it must be coincidence that this noise has appeared around the same time as the oil change. Next step is to take it to my local Indy and get them to see if they can find out the cause of the problem.

I was wondering if it could be the engine mounts, given that they've probably never been changed and its a 6yr old 106k mile car?

[TW]Fox · 16 Nov 2011 at 20:03

So when you said it was idling at 500rpm, you didnt actually mean 500rpm.

Sigh.

Scania · 16 Nov 2011 at 20:05

blun said:
I was wondering if it could be the engine mounts, given that they've probably never been changed and its a 6yr old 106k mile car?

Given its otherwise ok, it narrows it down to stuff like that if the vibration is still there.

That said, my 270k e39 has never to my knowledge needed new engine mounts, I'm sure I would not have missed that - its got a detailed FSH & I'm sad enough to browse it!

Is it a manual? - slight clutch judder?

blun · 16 Nov 2011 at 20:26

It is a manual. Could well be the clutch - as that too hasn't been replaced so is probably past its best.

Engine mounts seemed like a potential as they can be worn more by harsh conditions (obviously).. and there's not a lot harsher than sport suspension, 18" wheels, RFTs (switched to non-RFTs 2000 miles ago) and Yorkshire's finest pothole-ridden roads.

If it's either of these things its fine.. I didn't by a high mileage BMW expecting it never to need anything replacing. I was initially more worried that something to do with the oil service had caused a serious problem.

blun · 12 Jan 2012 at 19:12

Just an update if anyone's interested. It was the dual mass flywheel causing the vibration. New DMF and clutch (£600 at my local independent garage) and all is well again

Scania · 12 Jan 2012 at 19:27

£600 to sort a slight vibration? - I bet you wish it had been the engine mounts now!

Glad you posted an update, my pet hate is threads that never get an outcome - good or bad.

At least its sorted.

blun · 12 Jan 2012 at 19:41

I was hoping it would be something a bit less expensive, but it's done 110k so can't be too cross! DMF's are renowned for failing so its not a big surprise.

[TW]Fox · 12 Jan 2012 at 19:56

DMF's are reknowned for failing... on the diesels. Not so much the 330i..

blun · 12 Jan 2012 at 20:05

[TW]Fox;21018269 said:
DMF's are reknowned for failing... on the diesels. Not so much the 330i..

Being a bit of a mechanical n00b.. what's the difference between the DMF on a diesel and a petrol?

My understanding is that they're used on cars with high levels of torque to damp vibration (hence being more commonly used in diesels than petrols).

Overlag · 12 Jan 2012 at 22:55

blun said:
Being a bit of a mechanical n00b.. what's the difference between the DMF on a diesel and a petrol?

My understanding is that they're used on cars with high levels of torque to damp vibration (hence being more commonly used in diesels than petrols).

exactly that. A diesel generally has loads more torque than a petrol, hence they are more likely to fail on a diesel.