[CYL]

Hi, anyone experienced metallic rattling from the engine bay during acceleration? I have got this problem on my N52.

The noise is really annoying me, Took the car to 3 different workshops and tried to show them, but every time when I took the car to the workshop, the noise wasn't happening.....

The noise usually happens between 1500-2500 rpm, I am worrying anything major like pinging and want to fix it before putting on the exhaust (it will be harder to hear it with the new exhaust), I also can't pretend to hear nothing and just leave it.

One of the workshop helped me changing the idler pulley but the noise still exists.

Please help if you have come across with this or have any idea what could be the problem.
It's N52, NA, so, no wastegate.
Many thanks

[Scotty89]

Wastegate noise on a car with no wastegates?? Wow BMW, you've really out done yourself.

As it only does it during acceleration, I guess you can't put your head in the engine and pinpoint where it comes from?

[bmwheath]

I was going to say idler pulley, but could possibly be air con compressor bearing shot??
Cat convertors can also make a metallic rattle when the insides fall apart! Usually under acceleration too when the exhaust pressures are higher

[nash_86]

I've got this problem too! Except I installed catless downpipes last week and hence, I reckon mine's wastegate rattle??

[CYL]

Originally Posted by bmwheath

I was going to say idler pulley, but could possibly be air con compressor bearing shot??
Cat convertors can also make a metallic rattle when the insides fall apart! Usually under acceleration too when the exhaust pressures are higher

The idler pulley has been replaced...I am thinking if there is any other pulley being worn but should have been identified when they replaced the idler pulley unless they haven't checked the other pulleys?

The sound only happens between 1500-2500rpm, and when that happens, that's a feeling of lack of power and the car isn't accelerating. (I don't know how to describe it but you can feel it when you press the pedal)
Once the rpm gets higher, the car accelerates like normal.

Just really want to know what could be the problem and may try to bring the car to another workshop again and to check that particular area.

I replied to the post in the NA engine section but haven't got any answer back, so, really want to see if there is anyone else experiencing the same as I do.

[CYL]

Originally Posted by Scotty89

Wastegate noise on a car with no wastegates?? Wow BMW, you've really out done yourself.

As it only does it during acceleration, I guess you can't put your head in the engine and pinpoint where it comes from?

I have got replies before saying that it is the wastegate, just want to clarify that I have got N52 engine. I don't feel like the sound is like the wastegate sound anyway.

The sound is like a very rapid metallic sound, only last for about a second. Somehow it's like the sound from the Disel engine.
I also noticed that sometimes this sound happens on other old Japanese cars too when they accelerate after a red traffic light.

The sound is getting louder when it happens, and I can tell how weird it is when I see how people stare at my car..
Really want to fix this before anything goes worse....

[ATTN]

Take it Advan could be anything

[Socket]

Can you record the sound?

[CYL]

Originally Posted by ATTN

Take it Advan could be anything

I am in WA....
if I were in the east, I would have bought it to Advan or any other workshops that you guys go to straight away.

[CYL]

Originally Posted by Socket

Can you record the sound?

I did think of doing it but since it is happening occasionally, it's rather hard to record it considering the only recording device I have got is my iphone and I do have that much of memory left.
Thought of buying a GoPro and stick it on the bonnet when driving but feel like too expensive just for this purpose.

maybe I will try to record with my phone, just keep recording and deleting every few mins drive and try to capture the sound.

[CYL]

I tried to record a video today after work, the sound is at 0:04-0:05 sec
It sound in the video isn't as loud, as obvious and as long as to what normally is. But it's the sound that I am referring to, rapidly metallic sound.
Will try to record another one tomorrow.
Apologise for the poor quality. Many thanks for any help.

[CYL]

anyone? please help diagnosing..

really want some idea of what might be faulty so that I can ask the mechanic to check that specifically.

[CYL]

"Pinging can be anything from a loud knocking noise to a soft tinkling sound that is emitted from the engine. If an engine has a tendency to ping, it usually becomes first audible when operated in the lower rpm range and during acceleration. Pinging tends to fade away with increasing engine revolutions."


really worried about if my car is having this problem.

[juld0zer]

Old thread, but did you resolve it?

[xavi718]

Anyone knows whats this sound ? Like a compressor

[Socket]

Originally Posted by xavi718

Anyone knows whats this sound ? Like a compressor

No vid
just a big empty page sorry
Upload to youtube and then paste the link

[juld0zer]

Mine ended up being VANOS solenoids. No faults ever logged but it would cause a pinging type noise at certain rev ranges/load conditions, almost identical to when an engine would ping.

[xavi718]

someone solve the problem? I don't have codes yet but my car has lost power and it feels heavy as if it had a very heavy load, the sound would describe it as if the timing chain was loose or broken Vannos I also opened the engine cover but there was nothing broken or loose and it is consuming a lot of gasoline, I also inspected the brake piston thinking that maybe was tight with my rotor, but they were fine.