twin turbo

R

rjb1z4

Member
can any 1 help
i thought that the rattle i was getting was a loose heat sheild on the exhaust but my mec tells me its one of the turbo's
and it would be wiser to replace the 2 of them
im told it's quite a common problem
please advise
 
I didn't think it was that common, unless of course you have done mega miles and really pushed it, personally I would get a second opinion
 
rjb1z4 said:
can any 1 help
i thought that the rattle i was getting was a loose heat sheild on the exhaust but my mec tells me its one of the turbo's
and it would be wiser to replace the 2 of them
im told it's quite a common problem
please advise
Click to expand...

I’ve heard of earlier 35i/35is cars suffering from wastgate rattle, I don’t think it affected the performance/function of the turbo but was just an annoying sound :x
Rob
 
I have never had a twin turbo. However I have had three fail on my previous fiat. Never heard any kind of rattle. The things spin at such high speed they go bang before there go rattle. Plus that is generally accompanied by oily smoke out of the exhaust. Agree that you should get a second opinion.
 
Very common issue on all N54 engined cars. Infact so common I'd say it's just normal!

The wastegates start to rattle from 40k onwards. BMW made the problem less obvious with a software mod back in 2008 but you still hear it when in enclosed areas like garages and multi-storey car parks.

The rattling can be caused by leaking vacuum pipes so my first action would be to replace all of them. Just google "n54 replace vacuum lines DIY" and follow those threads, it's a 1 hour DIY at most.

You could also try doing the "Mr.5" fix. Google "Mr.5's wastegate rattle fix" and follow the instructions in that thread.

If neither things help then you can refurb the turbos with some new wastegates or just put some new pure turbos and enjoy some extra power :driving:
 
Mine has done this since new. Only when cold.

Had it back many times and the software update does help reduce the noise at the expense of notable turbo lag. (I didn’t realise how much lag until I coded my engine to remove it recently)
 
Mine sometimes has a rattle like that but it’s the exhaust flap. Try disconnecting the vacuum tube from the actuator and see if the noise goes away.
 
The classic 'wastegate rattle' on the n54 turbo's is a clearance matter on the guide bushings of the wastegate pins (so the bushings that go into the turbo housing where through the wastegate actuator rod goes).
The wastegate rattle can cause the wastegate to seal imporpely, causing loss of power, bad gas mileage and engine codes.

There are kits for this to repair this but fitting this is definately a specialist job (specialist as in turbo specialist, not a normal auto mechanic).
The bushing has to be drilled and hammered out an a new one has to be pressed in (including fitting new valve, lever etc). So thats quite a job. (just getting the turbo's out is quite a job, modifying even more, but it beats having to buy £3000 in bmw parts)

Repair kit: https://www.ecstuning.com/b-vargas-turbo-technologies-parts/wastegate-rattle-fix-repair-kit/vtt-n54-wf2~vtt/

More on the rattle and worn bushings:
[youtube]VQD6tITYH7k[/youtube]



So I hope you dont have this.
 
You must log in or register to reply here.
Back
Top Bottom