BMW M54B30 Rattle When Cold (E46 330i)

Soldato
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Right, this is driving me slowly mad. I'm posting here as enough of us here have had an M54BXX-powered BMW that someone might have experienced the same.

My car has a rattle between 1-2k RPM when the engine is cold, only on rising revs. I can't work it out.

I don't think it is terminal, as I've found 2 videos so far, one of which stated the car went on for a further 50k km (and no mention of the rattle being the reason that the car stopped going on, so I assume it was sold on or died of unrelated problems).

My car sounds exactly like the below when cold, in the same rev range. VANOS seals were done less than a year ago, and it's defo not the DISA flap rattling. Oil level makes no difference.



Anyone any idea what on earth this is? One of the posters of the above suspected oil pump, but didn't follow up.
 
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Danza can you hear the knock when the engine is warm on idle? My car seems to have a very faint knock that hasn't affected it's performance or oil consumption. If I put pressure on the engine cover towards the rear on the offside it goes away.

The knock in the first video sounds bad though.
 
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Rattle rings in vanos unit?

Not 100% sure it's not that. Just frustrating that the videos didn't state the cause as I don't really want to bugger about with the VANOS if it doesn't need it.

Danza can you hear the knock when the engine is warm on idle? My car seems to have a very faint knock that hasn't affected it's performance or oil consumption. If I put pressure on the engine cover towards the rear on the offside it goes away.

The knock in the first video sounds bad though.

Both those rattles in the videos sound exactly like mine. The first seems worse because it's outside the car. Mine doesn't do it when idling that I can hear at all.
 
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Crankshaft pulley, tensioners or water pump? Pop the aux belt off and run for a few (only) seconds see if it stops. If not, try listening with a piece of rubber pipe to your ear to try and narrow down the location.
 
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Get a metal/plastic tube and move it around different parts of the engine and put your ear over the other end to see if you can narrow it down further.
 
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I have a (crap) mechanic's stethoscope in my arsenal, but there's only so long the missus will tolerate sitting in the driver's seat, blipping the throttle while I faff about under the bonnet. I might try again this evening.
 
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New member, and the first thing I do is revisit an old thread, I know, but you may like what I have to say. I know this is almost 4 years since the last post, but better to bring up an old thread with a rarely described issue, than to start a new one, I think (although I will if we don't get anywhere with this).

I have exactly the same issue with my 2001 E39 530i. Its only on cold start up, only for the fast-idle period of time, and only around 1,000-2,000 (ish) rev range. And it started not long after I cleaned the... Wait for it... ICV (intake control valve). Which, after you clean and shake it, for those of you who know, will know that it makes this exact noise. Its not something anyone's considered in any 'cold start rattle' threads I can find. But... If anyone reads this, what are your thoughts?

If it ever happens when I'm not in a rush and have a cold engine, with an assistant to hand (to rev the engine while I investigate), I'll try the screwdriver technique to pinpoint the noise. But until then, I'd like to discuss others' opinions/experience/expertise on the matter.

Let the debate begin.
 
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New member, and the first thing I do is revisit an old thread, I know, but you may like what I have to say. I know this is almost 4 years since the last post, but better to bring up an old thread with a rarely described issue, than to start a new one, I think (although I will if we don't get anywhere with this).

I have exactly the same issue with my 2001 E39 530i. And it started not long after I cleaned the... Wait for it... ICV (intake control valve). Which, after you clean and shake it, for those of you who know, will know that it makes this exact noise. Its not something anyone's considered in any 'cold start rattle' threads I can find. But... If anyone reads this, what are your thoughts? Its only on cold start up, only for the fast idle period of time, and only around 1,000-2,000 (ish) rev range.

If it ever happens when I'm not in a rush and have a cold engine, I'll try the screwdriver technique to pinpoint the noise. But until then, I'd like to discuss others' opinions/experience/expertise on the matter.

Let the debate begin.

When I had mine, turned out to be a loose spark plug.
 
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Fair play, but I suppose the cold start or rev range might not affecr your rattle as much in that case. Plus I've changed my spark plugs once and checked them once again, since. So definitely not those. But always appreciate the feedback
 
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Never got to the bottom of this (wasn't a loose spark plug), and in April last year the car was written off. :(

I have a feeling it may have been piston slap as the car was burning oil and would chuff a little smoke when gunned.
 
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Ah, shame. But with the added symptoms of yours, I understand it was probably something more. But do you recall if you cleaned your intake parts, or maybe just the ICV at any point while you had the car?

I would like to know if anyone has any further thoughts on the ICV being the main culprit in my case (and the cases of the people from the 2 videos in the original post of this thread) . If you read back to the symptoms and the time/circumstances under which they appear, does anyone else agree? Because I'm convinced the ICV has to be the culprit, at least in my case.
 
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