318is engine noise/vibration ?

[hillbilly30]

Ok, so I've been blaming a rattling vibration type noise on my exhaust but I'm not sure now! I've been convinced it was loose exhaust baffles
It doesn't sound mechanical, it comes in at about 3000rpm and goes as it comes on cam at 4000rpm, I can't see anything loose.
It almost sounds like its inside the inlet manifold, do they all make that sound? Throttle body? Any hints welcomed!

[hillbilly30]

Timing chain tensioner?

[toby]

Worn timing chain tensioner perhaps.

[youtube][/youtube]

[toby]

Sorry, have now seen you guessed that too while I was distracted watching strange youtube videos...

[hillbilly30]

Thanks for vid Toby, after lots of googling it seems a fairly likely cause! Worth doing either way.

[Dave441cc]

Same on my iS .. it seems
to happen when a oil change is due ..
after a service it goes a˜„ been like it for
4 years

[hillbilly30]

Hi Dave, guess that would also link in with tensioner if its getting starved of oil as it gets older/thicker, oil change is also due on mine!

[DHFiS]

A rattle at 3000 rpm on an iS is the typical sign of a worn timing chain and gears. If you are very, very lucky a new tensioner will cure it for £30 but if it doesnt you are looking at £££££££

[hillbilly30]

Think I will pull the cover off tonight(this might be the excuse for an M52 ) would hope on a full history car with 93k the gears would still be pretty sound!

[DHFiS]

Some of the guides are plastic and I think the problem might be age rather than mileage.

I have an unused tensioner and bottom guide p/n 11311721419 if you need them.

The other 2 guide rails are about £110 for both.

[hillbilly30]

That's great, will see how it looks! Thanks for your help.

[hillbilly30]

A rattle at 3000 rpm on an iS is the typical sign of a worn timing chain and gears. If you are very, very lucky a new tensioner will cure it for £30 but if it doesnt you are looking at £££££££

Also worth being clear that's not a rattle as such, not a metallic sound!

[hillbilly30]

M52?

[hillbilly30]

So after the quick inspection
The tensioner was springing and oil filled, though the end was scored in the centre (is this ok?)
The engine does NOT rattle on cold start up or when hot.
The cam gear is pointy but prob not as bad as some I've seen on the google!
The chain and top end looked clean and well oiled
I'm now quite convinced that the noise that started this thread is the cam chain vibrating through under tension,

So, despite the tensioner being as described could it still be under performing and causing the issue?

Thanks for any help people! Much appreciated

[hillbilly30]

Think I'm gonna sent it to local specialist for investigation before I start ploughing money into it, but with worn cam gear I really don't think it's worth the spend?, would rather put cash towards the m52 conversion
I might go as far as a tensioner but I'm not convinced it will solve the issue DAMN YOU M42!!

[DHFiS]

You might get a cheap M42 here and hear it running before you buy.

http://www.ebay.co.uk/itm/BMW-E30-TOURI ... 3384baf843

If you have the money for the M52 then go for it.

[hillbilly30]

To be honest, I bought the "is" with the m52 in mind, only after the purchase I had thought of keeping it original as it was a nice example! So if the m42 comes out, it will be an m52 going back in!

[mark_i]

worth checking the metal plate that shields the HT cables from the exhaust manifold...

[baggimodo]

Dhfis I was quoted closer to £200 for the guide rails today from the stealers. Are there any other suppliers?