My car has developed a cold start rattle and Im having some problems diagnosing it

Car details: Feb 2004, MCS JCW 210 kit, Air con, newman cam and a few other tuning parts - details available via sig if needed- or feel free to ask.

It is currently in the garage getting looked at but the mechanic isnt currently able to pin point the problem and we are a little stumped on what it is...

Details as follows:-

- The rattle is only a cold start rattle - goes once the car is up to operating temp.

- Located on the drivers side and is loudest when listening through the drivers side front wheel.

- Garage has listened to the engine with some sort of probe and no rattling is heard from within the engine or the timing chain - although he did note the slightly rough idle from the newman cam - other than that its fine.

- Aux belt tensioner has been replaced as that was leaking - orignally thought this was the problem but with the new one on, and a new belt, the noise is still there.

- Garage noticed that the crank pulley is starting to wear with an area about 1inch long where the rubber is coming away/perishing from the metal.

- He ran the car with the aux belt off and there was no rattle so its something driven by the aux belt which stops rattling when the engine has warmed up.

I need some help with suggestions as to whats wrong with it as Im stumped and the garage is too - going to try another cold start in the morning and some sort of lube on a few parts to see if something has gotten too dry that should be lubed up

Feel free to ask questions if it will help you with attempting a diagnosis ...

Thanks in advance

 

maybe a sound clip or video would help
i have a loud ticking/tapping noise of some sort, mainly in the morning only. pretty loud, but like yours it does go away once car is warmed up.
hopefully you can get the sound fixed

sorry i'm of no help.

but the dealer blamed my tapping/knocking/tapping noises on my upgraded pulley..they said the pulley is basically wearing everything out quicker? and making it fail? dunno, something like that.

 

Video of noise on first start just after its been taken out the garage... not great i know but it lets you hear the sort of noise im taking about...

 

thanks - i was gonna add vids when i got home from work, see above as they are now there

Your noise; sound like this vid?

 

At the least you need to replace the crank pulley as it is failing and this may well be the cause of the noise.

 

hmm mine does kinda sound like that..
i think the dealer told me that the crank pulley and belt tensioner isn't covered under warranty because of my upgraded pulley..
they said the upgraded pulley is putting extra wear & tear on all the other items..
thanks for the help keano..as i am taking my mini in to the dealer next week..i will list this as a possible problem to check for..
(sorry to sorta hi-jack your thread)

but does your noise come from the engine bay at all? that's an odd sound to be coming only from the driver's wheel well

 

Well considering he is in the UK it may not be so odd......

 

Could be as titled Keano - plastic collars on the valves tended to get brittle on older cars .

 

have you tried pushing in your clutch? My '04 MCS sometimes has a decent rattle loudest by the driver's side especially on cold mornings and it turns out to be the dual mass flywheel/clutch setup chattering.. Nothing to be worried about though. Next cold start, try pushing in the clutch and see if the sound goes away. Some quick research told me the design of the setup is to blame, so don't be worried about either part letting go.

*note* we have different driver's sides

 

I have the same situation, pushing in the clutch quiets her up.

 

Sorry for the confusion - yes Im over in the UK so drivers side is on the opposite side to you guys in the states Sorry lol

Got the noise sorted in the end. Changed the crank pulley for a +1% ATI super damper just so that was eliminated.

The rattle was however coming from the timing chain tensioner - changed that and all was sorted - total cost for the tensioner with labour was circa £90... pretty cheap really...

Thanks to those who tried to help