Engine Noise - idle doesn't sound good

daveg

Active member
 Leatherhead, Surrey
Hi everyone,

I notice a lot of noise at idle and not sure if it's supposed to be there. Notice it most when pulling up at home with roof down as it bounces off a wall next to the car.

I have tried to ignore it but can't. There are two noises:

1) Louder chatter front lower down - others have described as pulley noise.

2) Tapping from somewhere near top of engine. Almost sounds like a little air compressor? Hard to capture and noise 1 drowns it out on videos.

[youtube]G-sxUx6IUzI[/youtube]

Anything to be worried about or need further diagnostics?

Thanks,
Dave
 
Potential DISA??

Though it sounds a little low down an metallic for that. Does it still have that sound at higher revs? and when warm?

Im sure some of the experts on here will have a good idea.
 
I uhm wouldn't drive it making that sound. Sorry I don't have any better info, but I'd get to an indy asap.
 
definately don't drive it, is it always like that? i had a similar noise but only once, there is a fault on the hydraulic oil lifters or something that causes a tappet sound, i will find post on here later for you
 
Some worrying responses there.

Both Auto Tech Telford and local BMW indy 'Specilist' said they couldn't hear anything to be worried about.

It doesn't make it at cold, I only really notice it when pulling up after the drive home with roof down.

I checked/cleaned the DISA a few months ago and tried running engine with the cable disconnected as recommended on here but made no difference.
 
I would check the DISA for any play in the flap.

[youtube]<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/SNJ7qUa_FbU&hl=en_GB&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/SNJ7qUa_FbU&hl=en_GB&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>[/youtube]
 
Thanks for your input guys.

The main noise heard in the video isn't there when cold. That's why I only notice when pulling up when home. On the road it's drowned out by the intake noise.

It is affected by the engine RPM, lightly rev the engine and it speeds up too.
 
Would you say it was similar to a water pump noise? If so, I've been thro the same process.

It runs like a swiss watch when cold - but when warmed up it rattles. If mine is parked nose up, the noise is greatly reduced, nose down, it sounds bloody awful.

The BMW guru at the main dealer reckons its just a bit of backlash in the vanos gears and as such nothing to worry about (he says) The AUC warranty would not cover the replacement for a bit of wear. (35k)

I've renewed the warranty just in case something lets go - Its getting a good run down the autobahn at the end of August - I may have more info then!
 
Sounds like mine ronk, not a wisper when cold.

As a side note that may be of relevance, I'm getting "Exhaust Cam Position Actuator Open Circuit - Bank 1" code P0013 :cry:
 
Mrs CJ who's sat near me glanced over while I was playing your clip and observed she didn't know Z4 did a diesel :poke:

Still I can laugh mine sounds like a bag of nails on idle right now :thumbsdown:
 
Thanks Mrs CJ :D One of my colleagues also remarked it sounded a bit like a diesel with all the noises.

It's made better by
A) I can't hear it whilst driving
and
B) The drive is so damn good :evil:

Still, the replies have shown me maybe I shouldn't be ignoring it given prior advice and am arranging to have it listened to.

Thanks all,
Dave
 
Dave you cannot ignore that, it's not tappets though (HVA's) and it does sound like bearings on water pump to me.
 
A failing DISA does NOT sound like that....

But if you really want to check it, the DISA is only held on with two bolts. It only takes five minutes to remove and check the play. To know how the DISA works, go to one of my post from last year.

Your issue DOES sound like a rotational noise. Srhutch may have it with a water-pump. Water-pumps are known problems or as I said in my PM that it could also be a belt tensioner.

For reference, see these links.
The water pump is no. 1 : http://www.realoem.com/bmw/showparts.do?model=BT33&mospid=47798&btnr=11_2180&hg=11&fg=35
The belt tensioner is no. 2 : http://www.realoem.com/bmw/showparts.do?model=BT33&mospid=47798&btnr=11_3416&hg=11&fg=18

You can to do a test of both water-pump and belt tensioner. Remove the belts, and rotate the each one by hand. They should feel smooth. If you feel any grabbing or excessive play, that may be the culprit.

If you had a mechanics stethoscope, you can pinpoint the noise down to an exact area, and then the offending part. This may be the best way to figure out what the issue is without throwing parts (money) at it.


The M54 motor is not noted for having hydraulic tapped issues. That is mainly with the N52 and N54 engines, like on the Si and the newest fix from BMW is a new head.
 
Just as a minor correction the belt tensioner pulley is actually part 11.28.7.841.228 not part 2 in the link above, whic I think is the tensioner mechanism

I know as I purchased and fitted one 2 days ago to cure a similar noise having found slack in its bearing. Sadly it's not that and I'm after a waterpump as the next culprit.

Price of the pulley is £24.49 after 10% discount.

If you plase a 16mm (iirc) socket on the tensioner adjuster and push it to the right it loosens the belt and you can with dexterity feel the slack in any of the bearings or ancills.
 
My car went into the dealer last year with this noise albeit not as bad. I suggested to him that is was a water pump noise. It sounded very much like an old BMC 'A' series! The belts were removed and all the rotating bit checked. They were all found to be play free and smooth running. The front crank damper/pulley was changed as there was some evidence of a degree of rubber extrusion and a new belt was fitted. The noise was no better!

They (the dealer) suggested that I gave it a few more miles, but as this is a 2nd car / toy for the sunshine days, it didn't get a lot during December to March!
As the AUC warranty expired in March I asked for the visiting BMW trouble shooter / guru to have a look at it and as I said in my earlier post, he said "nothing to worry about - vanos." The AUC warranty will cover broken / failed parts.

I tried another BMW dealer for the cars MOT prior to the warranty expiry - He also said that the noise in my car was the vanos and that some cars do and others dont!

Have you tried pointing the nose of the car uphill to see if the noise is reduced? Mine is acceptably quiet nose up - This suggests to me that some sort of end float exists.

Do the cam position fault codes seem indicate a vanos related problem?
 
It might be worth you looking at this old post:-


Engine Idle Noise 3.0 i Pre facelift


viewtopic.php?f=3&t=13067&p=201416#p201416
 
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