[Ianed8484]

I've been experiencing a rattling noise on start up and when coasting or deacclerating. Local indy thinks it may be timing chain related and suggested replacement. 320i 2018.

I'm not 100% convinced. Any help appreciated. Link to a video with sound below

https://youtu.be/uiZk839acHU?si=DzqZ8tFmVXQeDgOS[/url][/QUOTE][/IMG]

[danb1979]

Not the best video really... Can you get one with the engine running and you filming it with the bonnet open etc?

Do the rattles increase/decrease with revs etc?

What oil/filter changes has it hand in your ownership and before?

Always thought the N20 gave off more of a high pitch whine when the chains having issues...

[Allworth]

What is car mileage, and as danb suggested you better capture sound under bonnet.

[Ianed8484]

Car is currently in the garage, I'll get another video when I pick it up tomorrow.

Milage is 63000, serviced every year, there was an 18 month gap from 2022 to 2023. I bought the car June 2023 and it was serviced then

Transmission seal replaced by indy.

Cam shaft sensor replaced by bmw

Been in for diagnostics and health check with bmw twice since ownership. They previously didn't pick up on timing chain issues

[Ianed8484]

The rattle increases when deacclerating and goes away when driving above 2k revs. This is intermittent though and can sometimes be hard to replicate if trying to

[danb1979]

Originally Posted by Ianed8484

Car is currently in the garage, I'll get another video when I pick it up tomorrow.

Milage is 63000, serviced every year, there was an 18 month gap from 2022 to 2023. I bought the car June 2023 and it was serviced then

Transmission seal replaced by indy.

Cam shaft sensor replaced by bmw

Been in for diagnostics and health check with bmw twice since ownership. They previously didn't pick up on timing chain issues

Get a fresh vid up with you filming it whilst on tick over with the bonnet open (and maybe get someone to rev it for you a bit) and we'll go from there

My pals had a 328i in recently and it was a loud whine when being run; that was a fubar'd timing chain

[M80]

Always thought the N20 gave off more of a high pitch whine when the chains having issues...

OP's car would be a B48 wouldn't it Dan?
TBH that start up sounds just like mine and any other B48 3er I've heard.
It's all Massey Ferguson for about 20 seconds and then quietens down.

[danb1979]

Originally Posted by M80

OP's car would be a B48 wouldn't it Dan?
TBH that start up sounds just like mine and any other B48 3er I've heard.
It's all Massey Ferguson for about 20 seconds and then quietens down.

It will be; on my phone and read it as a 2015...

And yes; the B48s are noisy at times aren't they...

[M80]

Originally Posted by danb1979

It will be; on my phone and read it as a 2015...

And yes; the B48s are noisy at times aren't they...

When I was looking for my touring, the first one I saw (at a BMW dealership) sounded like a tank on cold start-up The sales guy gave me the "They all do that Sir...." spiel, but it turns out he was actually right.
Who knew

[danb1979]

Originally Posted by M80

When I was looking for my touring, the first one I saw (at a BMW dealership) sounded like a tank on cold start-up The sales guy gave me the "They all do that Sir...." spiel, but it turns out he was actually right.
Who knew

They do; that was my first reaction...

One of the lads that has quite a few niche cars that my pals look after has an E60 M5; that's deffo a tractor on start up haha Even with the Supersprint exhaust; it sounds a bag of spanners on cold start!

[M80]

Originally Posted by danb1979

They do; that was my first reaction...

One of the lads that has quite a few niche cars that my pals look after has an E60 M5; that's deffo a tractor on start up haha Even with the Supersprint exhaust; it sounds a bag of spanners on cold start!

All that wastegate-opening trickery to warm up the Cats doesn't help

[TurboWeasel]

Should be able to correlate cam and crank position (with ISTA) to gauge how slack the chain is.

N engines have a chain wear indicator tool available.

[Ianed8484]

Indy has quoted 2.3k to replace timing chain, they have said I could try an oil flush and see if that helps. Would this make any difference??

I get the car back tomorrow so I'll post another video with the bonnet up.

A friend has suggested getting a 2nd diagnostic.

[danb1979]

Originally Posted by Ianed8484

Indy has quoted 2.3k to replace timing chain, they have said I could try an oil flush and see if that helps. Would this make any difference??

I get the car back tomorrow so I'll post another video with the bonnet up.

A friend has suggested getting a 2nd diagnostic.

Why does the indy think it needs a new chain/guides? The B48s are nowhere near as prone as the N20s before them etc...

Deffo get a 2nd opinion ASAP

[Ianed8484]

They said "it made an awful rattle on start up which sounded like it was coming from the timing chain"
They were concerned over service history as on bmw database it hadn't been serviced for 24k but as previously mentioned receipts would indicate there was an 18 month gap between service. It could just be it wasn't recorded on the database.

The rattling sound I originally took the car in for on diagnostic seemed to go away the more I accelerated, surely if it was timing chain the sound would get worse?

I think a second opinion is definitely the right thing to do. The indy I have used is usually pretty good but I'm not 100% convinced on this occasion

[Pond]

If you have an intermittent 'rattle' which is largely rev related, I would have a good look for something being physically slightly loose in the engine bay TBH before replacing an expensive cam chain. 63k miles is very low for an N20, let alone a B48.

I had my daughter's Mini booked in for a cam chain replacement because of the dreadful noise it was making. Turned out to a damaged aux belt which was whacking against something on every revolution. Sounded much more serious than it was.

[Ianed8484]

Originally Posted by Pond

If you have an intermittent 'rattle' which is largely rev related, I would have a good look for something being physically slightly loose in the engine bay TBH before replacing an expensive cam chain. 63k miles is very low for an N20, let alone a B48.

I had my daughter's Mini booked in for a cam chain replacement because of the dreadful noise it was making. Turned out to a damaged aux belt which was whacking against something on every revolution. Sounded much more serious than it was.

Thanks for your input. 2.3 k is definitely more than I would want to spend. At that kinda cost I'd consider selling. I think a 2nd diag is the best option

[Ianed8484]

Thanks to everyone's input so far. I'll update when I get the car back tomorrow