Approved used CLS M272 issue

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MB Enthusiast
Feb 14, 2009
:( Grab yourselves a bucket of popcorn and a cup of tea.

I've owned my petrol CLS for 6 weeks now (purchased from a main dealer with a tier one warranty) and unfortunately have a problem. Despite very careful research and opting for a late model car with an engine number (5xxxxx) way after the reported timing gear/balance shaft problems, last week I got the dreaded engine management light. This 1 private previous owner from new (registered to a lady in a very upmarket place) car with FMBSH and serviced every 10,000 miles is 4.5 years old and has covered 41,000 miles. It is supposed to have the hardened timing gear/balance shaft.

I went back to the supplying dealer to diagnose the issue as soon as the engine management light came on last week (I had to book it in for a vehicle health check to have it diagnosed). The checks were very thorough and confirmed my worst fears that a worn out balance shaft and timing gear resulting in slack timing chain had triggered the engine management light. 25 hours labour plus some pretty expensive parts was the estimate. When doing the vehicle health check the technician/manager didn't realise I had bought the car from them and they were rather surprised after I told them after hearing what was wrong with the car.

They told me the car is safe to drive in the meantime and no further damage will be caused by driving it. Please can one of our forum technical experts confirm whether this is the case?

Logic tells me clearly whilst the vehicle still runs surely there must be a risk of further damage to the engine through running non-optimal timing. I gather the engine is also likely to be contaminated with swarf internally due to the damaged timing gear and balance shaft. Other symptoms are exhaust pipes covered in soot within a few dozen miles of cleaning thoroughly (indicating very rich running) and very poor fuel consumption (22 mpg indicated at a steady 60mph for 10 miles). The engine light was reset last week but came back on the day later.

Now for the controversial bit. They were supposed to be submitting a warranty claim for me straight away but their manager who normally submits the claims was out of the office until today. I got a phone call today saying they need to wait until September to submit the warranty claim. Their reason is because I have only owned the vehicle for 6 weeks and 1000 miles, from experience the guy that submits all warranty claims from this dealer believes the claim will be thrown out if submitted so soon after purchase.

However - is this really my problem? They sold a car with a major engine defect which has appeared within 5 weeks/1000 miles - it's not like the CD player isn't working or something trivial. It's also a well documented defect. If the warranty company won't pay I would think the dealer would have to foot the bill anyway?

If someone could please verify the "no further damage will be caused" statement I would be grateful. I plan to keep this car as least as long as my old CLK (6years+) and I am currently afraid to use it for fear of causing long term damage which will shorten the life of the car and won't manifest itself for several years when the vehicle is well out of warranty.

Not your problem, they need to sort it and not make you wait until september....

There is no definitive answer on the driving question, as without inspection its difficult to tell how worn the shaft actually is, but if the light has just come on id say the car should be safe to drive for the time being.
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This is totally unacceptable, if they wish to wait over 6 weeks before submitting a claim then insist on a like for like courtesy car free of charge in the interim. and until fully repaired to your satisfaction.

Or, just insist on them fixing it now whilst providing the courtesy car to save them the bother of attending court! Your contract is with the dealer, the car is not of merchantable quality and the argument over who pays for the repair is between the dealer and MB UK.
That's disgusting. There's no logic whatsoever in making you wait, Surely the most sensible course of action is to get the car in for repair now, before it get's worse and may need even more attention. This sounds dodgy to me and I certainly wouldn't put up with it.

When I had the main bearing failure on my CLS there was no hesitation by the dealer in taking it in and fixing it (and at MBs cost) as soon as possible.

Nothing less is acceptable. (or to give you a decent courtesy car while you wait for them to act..)
Ask to speak to the dealership principle. Insist upon a courtesy car, impress upon him that this situation is not acceptable and you will be speaking with MBUK if you are not satisfied.
I wonder if the reason they want you to wait is that they don't want to carry the can for the repairs.

Wouldn't surprise me to find that during the early period of ownership MB would make them at least partly liable for anything they'd "missed" during the Approved inspection.
Refuse to wait. I got caught out like this when I bought my AMG. The selling (non Merc) dealer sold the car with full warranty. When the AC compressor failed he asked me to wait a couple of weeks before making the claim. This was as I understood it to ensure that the warranty company had all my paperwork on their system.....WRONG. It was so that the dealer could claim that he had now way of knowing that the car was faulty when he sold me the warranty.

The warranty company subsequently refused to pay out 800 quid loss to me.

Sounds like you have a similar issue. i.e. the dealer is attempting to put distance between the sale and the start of the problem. "We could not have known as he had been driving the car for three months"

Tell your dealer you want the car sorted now with no haggle and no delay or your next call is the solicitors/trading standards office.
So that means anyone with this engine is at risk from worn balancer shaft sprocket?, as your engine serial number is well above the apparent sprocket update. What size engine have you got??? i spoke to 2 independent merc specialist in manchester, one said he has only encountered this issue once and the other said that he's never come accross it but knows there is an issue in america. It seems that this problem is rare in the uk, but don't quote me on that. Whats worrying is that yours is a late model which is supposed to have the upgraded sprocket :-/

I wonder if the reason they want you to wait is that they don't want to carry the can for the repairs.

Spot on, they probably have some kind of 6 week period where they have to pay to rectify before the warranty company starts covering the vehicle.

If they are getting funny demand a refund and stop using the car, notify them in writing of course.

I wonder if the reason they want you to wait is that they don't want to carry the can for the repairs.

Wouldn't surprise me to find that during the early period of ownership MB would make them at least partly liable for anything they'd "missed" during the Approved inspection.

This certainly used to be the case.... which is why I am laughing at comments on other threads that dealers do not do the approved used checks...

Seen many a px sent to the auction as it would cost too much to prep to approved used standard.
Drop the car off, insist its fixed and they do not contact you until its fixed, and demand another car to use in the mean time.

Alert them to this thread, and send MBUK a letter of complaint, and CC the dealer and hand deliver it.

Or ask for a full refund then and there.
More importantly, never buy from this bunch of jokers again!

Thanks for the feedback so far. Whilst a refund on the face of it may seem attractive the fact is I have px'd my old CLK for peanuts so would be in a worse position. I suppose it could be a last resort.

A refund would probably be more attractive to the dealer than shelling out several thousand quid fixing it if as suspected they are going to foot the bill due to it being so soon after sale that faults have emerged. They could move on the CLS at auction and maybe only lose £1000 or so.

The current issue aside this car has a brand new set of conti sport 3 tyres, recent all round discs and pads, giant turbine stylie AMG wheels etc etc which a replacement CLS I buy may not have so could well cost me more like for like. Maybe not, who knows.

Anyway as a first step tomorrow I will politely give them the option of fixing it as soon as reasonably possible (or providing a loan car through to Sep) and highlight that if the warranty company will not foot the bill it is not really my concern - the car needs to be of merchantable quality 5 weeks into ownership. I would prefer to resolve speedily and amicably if possible.

We will see what happens!
Update for anyone interested.

The manager at the dealer got back to me today having run my predicament by their DP and would like me to come in for a face to face meeting to discuss getting this resolved to my satisfaction. They would like their workshop manager to be present who is currently out on holiday so suggested this time next week. Probably crazy for me to let this simple problem drag on for another week but I will give them the chance to hopefully put things right. This will be the last opportunity they have to do the right thing, if this avenue fails or there is any nonsense it will be MBUK as next port of call and I can't imagine they would have much wriggle room on this issue.

We will see what happens - ideally it would be good to just get this car fixed pronto and get on with my summer.

However I have also been thinking more about the refund option and maybe it wouldn't be a bad thing in the unlikely event can't get any sense out of anyone. The fact is the timing gear has given up at a pretty low mileage which does kind of suggest the car has been subjected to heavy usage (my guess would be lots of hours idling in urban traffic). On the flipside I suppose getting it fixed should allow for say 80-100k of normal usage before it eats the gear again, which is longer than say if I bought a 60k miles car which may only have 20k left in it! :doh:
A little update.

Went in today for a meeting. Workshop manager back from holiday and wanted to test drive the car as he hadn't yet examined issue. Went for a drive with me present as passenger. He then sent the car in to the workshop where some tests were done for 10 mins.

They now believe the balance shaft/timing gear is perfectly fine and think it is just a cam sensor that needs to be changed. I will drop it in for this when they get the part.

Thing is I don'tget how they can be so certain without dismantling to see the gear/chain and why did the original guy come to the conculsion it was the full blown timing gear issue.

The service bulletin for these timing gear issues describes a half a$$d fix where in the early stages of wear they replace the cam sensors for ones with greater tolerances that basically don't trigger the engine light/fault codes until the gear is well and truly worn out 12+ months down the line then the customer gets to pay the bill instead of MB for the engine out job from my understanding.

I do hope my sensor is a different part/problem entirely.

This is now tricky as I probably have no recourse under either tier 1 or sale of goods if there is no evidence that the part is defective (if indeed it is) without taking the engine apart. Other than the original engineer's notes/computer printout saying that the balance shaft/timing gear is defective.

They are just fitting the newer sensors with greater tolerances.
This is the MB approved course of action so not much arguing with it im afraid.
Cheers Jay. As I suspected. So maybe 20k miles before the engine needs to come out if I'm lucky.

I could drive that distance before the tier 1 expires in the hope it fully wears out but that would be a fairly costly approach .

I could extend the warranty at the end of the year.

I wonder if I have any recourse to hand the car back. Just because the bodge fix is mb approved doesn't mean it complies with sale of goods. Knowing I need major engine work in the near future on such a new car really grates.
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It is annoying but remember that many have reported doing 100K + with the new sensors installed..

I would just ensure you always have a good warranty that covers manufactural design defects..
Annoying indeed!

Thing is I have a detailed vehicle health check that was carried out by the dealer which in no uncertain terms says the parts are worn out and need to be changed (this was given to me before they realised I bought the car from them).

There are a number of other defects with the car too.

Hence I am going to pursue this somewhat.

4th visit back to the dealer in 6 weeks tomorrow..

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