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Hi All,

After 3 yesra of ownership, I waved a sad goodbye to my Z last night. Alas, just 1 hour later, the new owner called me to advise that it had developed a strange noise (it may have been there for some time, but I'd never noticed it and he only noticed when parking it up in a small underground garage).

The car was taken to a local BMW specialist today who,advised the noise was coming from the timing chain area and it could mean chain replacement etc with a bill into 4 figures.

Now, I may be wrong but this sounds like BS. The N52 (the car is a 2.5si) is, to the best of my knowledge, almost bullet proof in terms of chain reliability, so I cannot see that potential failure is likely. The only chain related issue I can find is the occasional need to replace the tensioner.

Symptoms are a rattling noise when the engine is warm and the revs increase above idle, then the noise disappears higher up the rev range. It doesn't make the noise when the car is cold or idling. The engine has only done 59,700 miles and has always been serviced correctly, including an oil change less than 100 miles ago.

Does anyone have a view on the potential cause ?

Many thanks, James

I've never read anything about cam-chain issues with the N52 engine, although obviously that doesn't mean it will never happen. But having owned a 1 Series with the N47 diesel engine previously that is pretty well known for such problems I did loads of searches!

No idea what the "issue" may be, other than BS as you say.

But if the new owner called to say it "had developed a strange noise" and it was a private sale then it is the new owner's problem.

Murky waters buying + selling used cars privately but he presumably viewed , inspected & even drove the car before agreeing to buy it ? He then happily handed over his cash to make the car his ? Which it now is this might sound harsh but whatever problems there may or may not be are all his now , he may well have ragged the car to the max through every gear its no longer not your concern imo

absolute BS! It sounds like maybe the lifters or maybe even dual mass? Wont be the chain,

as above though Caveat Emptor - its not your problem anymore

Hi All,

I agree it is not my issue directly, but I always work on the basis of 'do unto others ...' and all that.

My gut feel here is that a new chain tensioner will sort out what I now believe is 'chain slap'. Has anyone changed the chain tensioner ? If so, why ? And did it resolve things ?

Thx

The garage have advised "it could be". That's not a diagnosis. Sounds like he is being mugged off, so I'd suggest he get another opinion especially as I've not heard of any chain issues.
If you were being honest and had no idea along with it having "developed" after purchase then it really is unfortunate but equally not your problem.

I would want some sort of proof, i wouldn't go on a complete strangers word or that of a garage i didn't send it to. I agree with others that it smells funny however i would have it sent to a garage of my choice for investigation, that's if i even entertained it at all.

New to these cars and engines myself, but from what I’ve learned so far, the DISA or VANOS are more common sources of rattles.

Timing chain issues are incredibly rare on the N52. Much more common is HVA noise due to air in the hydraulic lifters. Car needs to go for a good blast down the motorway which usually sorts it. This issue does seem to be a little dependent on oil characteristics and if you have just changed the oil then this seems quite coincidental. What oil did you use?

All,

Have checked with the specialist and the car was only taken in and a 'quick listen' undertaken. The noise was narrowed down to the front end, probably the timing chain and it was indicated that the 'worst case' could be chain replacement. So not really BS, but a worst case painted that in reality is extremely unlikely.

The oil change, less than 100 miles ago, was completed using a Mann filter and Castrol Magnatec 5-30W.

Could this be serpentine belt related, pulleys, tensioner etc ? The car has done 60k, so could be due a belt (anyone know the change interval - 80k ?), but I thought the tensioners and pulleys etc squeak, or squeal continuously when failing, not at certain rev ranges. I am happy to stand corrected though, so again all thoughts are welcome.

Very unlikely to be the serp belt. I still think HVA / oil related is most likely but hard to say for sure without hearing it in person. Nothing wrong with Mann filters or Magnatec 5W-30 (apart from it's not really a full synthetic) but did you do the change yourself or was it a garage? I only ask because it can be a right bitch getting the right oil level with the silly electronic dipstick.

EDIT: apologies I see that Magnatec 5W-30 is indeed now fully synth.

I have never seen a chain prob on the N52...

The valvetronic mechanism can get noisy though and isnt uncommon.

Sounds like a skeleton having a w@nk in a biscuit tin...


If you got half decent money for you car,offer him £300 to be out of your life,if he bid you low and the car was cheap then i wouldnt feel obliged..

Thanks for the additional replies.

I did the oil change myself and put in bang on 6.5L (exactly what a BMW dealership would do). The dash says the oil is full (i.e. top of the electronic dipstick) and I believe there is an electronic overfill warning anyway - can anyone confirm ? I also did a flush with circa 1L of Magnatec to clean out all of the old stuff.

I'm going to look at the car tonight. Will be checking belt, heat shields etc.

Cheers, James

I think the electronic dipstick only refreshes every 20 mins, and even then only when oil temp is over a certain value and there is not major yaw, steering input etc. Very easy to be misled by it. Hence you can easily put far too much oil in and it won't be reported. But 6.5l sounds good.

Hi All,

Been to see the car and am confident that it is not belt or chain related. If sounds to me like a rattle within the air intake system. As this is an N52, could this be the DISA valve and does the 2.5si N52 have two or one ?

Thx