Approved used CLS M272 issue

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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.

Cam sensors are quite common on petrol cls's(mine went on the v8 500 luckily under manufactures warranty & no issues since)if it's the other(much more expensive)issue you mentioned then that is specific to the 350 petrol 219's-hope it's the cam sensors.
 
Cam sensors are quite common on petrol cls's(mine went on the v8 500 luckily under manufactures warranty & no issues since)if it's the other(much more expensive)issue you mentioned then that is specific to the 350 petrol 219's-hope it's the cam sensors.


Thanks - I think unfortunately it is unlikely to be anything other than the initial signs of the major engine defect though in this case.

Scenario 2 of this Mercedes tech bulletin document indicates "improved camshaft adjustment solenoids" to be fitted. The improvement basically tolerates the incorrect timing without reporting a fault code until the timing gear/balance shafts are totally trashed:

Mercedes Engine TSB

Scenario 1 describes the full fix which will need to take place when this eventually happens.

Interesting that engine numbers up to 759427 may be impacted rather than 468993 as previously suggested elsewhere on the forum.

The best or nothing?!
 
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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..

I would be inclined to get in touch with MB and provide evidence of the conflicting advice from the dealer and ask them inspect the car to verify which version is correct.

Sadly the experience reported is not good from the perspective of the AU scheme because at it's heart it's all about trust in the brand and its dealers.

There are three aspects here based on the information you're providing.
  • The initial advice was simply wrong. Not good for the dealer's competence.
  • Or the dealer's service department was trying it on. Not good for the dealer's ethics.
  • Or it is right. Not good for the dealer's ethics. And a travesty of the AU scheme.
Basically MB should provide a second opinion independently of the dealer. If they can't or won't the AU scheme has failed you.
 
I would be inclined to get in touch with MB and provide evidence of the conflicting advice from the dealer and ask them inspect the car to verify which version is correct.

Sadly the experience reported is not good from the perspective of the AU scheme because at it's heart it's all about trust in the brand and its dealers.




There are three aspects here based on the information you're providing.
  • The initial advice was simply wrong. Not good for the dealer's competence.
  • Or the dealer's service department was trying it on. Not good for the dealer's ethics.
  • Or it is right. Not good for the dealer's ethics. And a travesty of the AU scheme.
Basically MB should provide a second opinion independently of the dealer. If they can't or won't the AU scheme has failed you.


I think this is spot on. Unless something crazy happens when I visit the dealer tomorrow I need to write to MB and ask to have this car independently inspected at another MB dealer.

Should add - I am generally not into the whole compensation culture, but I don't think it would be unreasonable to ask for another 12 months warranty on this car at the very least based on my experience to date.
 
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The hassle of finding out whether or not your car will be due for a very expensive overhaul at some point in the future and then the cost of protecting against it and worrying about it...
Compared to just asking for your money back...
IMHO the money option is the best way.
 
The hassle of finding out whether or not your car will be due for a very expensive overhaul at some point in the future and then the cost of protecting against it and worrying about it...
Compared to just asking for your money back...
IMHO the money option is the best way.


Agree - it is getting to the point where it is not worth the hassle.

4th visit tomorrow where they will fit a new cam sensor and grudgingly tackle some of the other issues. I will no doubt have to go back again.

However technically according to UK law they are entitled a few goes at fixing it before I can reject under sale of goods act.

I haven't yet asked directly if a refund is an option (apart from an email where I said it could be a last resort). I suspect if I asked about a refund they would say no.

At which point I would have to resort to legal channels (not too much hassle as good friend/neighbour is a county court judge).

But yes in an ideal world - refund, take the cash, find a decent Merc. Anyone any experience having a refund 6 weeks into ownership? I am over the 4 week exchange point unfortunately (faults only appeared at 5 weeks:doh:)
 
The right to a full refund without any questions asks is generally 3 - 4 weeks (from what I have seen on the internet) and since your fault appeared later, they are allowed to try to either repair or replace it. Fitting a less sensitive sensor is avoiding the issue that the engine will at some point NEED an expensive going over. Alot of money is at stake. If it were me I would hire a solicitor to force a refund.
 
Scenario 2 of this Mercedes tech bulletin document indicates "improved camshaft adjustment solenoids" to be fitted. The improvement basically tolerates the incorrect timing without reporting a fault code until the timing gear/balance shafts are totally trashed:

Mercedes Engine TSB

Scenario 1 describes the full fix which will need to take place when this eventually happens.

Interesting that engine numbers up to 759427 may be impacted rather than 468993 as previously suggested elsewhere on the forum.
I disagree with your interpretation of that TSB. I believe that there are two separate issues:

  1. M272 Engines up to serial# 2729..30 468993 suffered from a material manufacturing fault affecting the the balance shaft sprocket; This component was (is?) produced from sintered steel and the sintering process had not been carried out correctly. This was corrected from that engine serial# onwards
  2. Separately M272 Engines up to serial# 2729..30 759427 can suffer a failure of the camshaft adjustment solenoids. It does not follow that there is an underlying problem with the balance shaft sprocket on engine serial#'s 468994 to 759427
It would appear that the dealer initially mis-diagnosed the problem, having also misinterpreted the TSB.
 
Sorry, I missed out another salient point:

The M272 engine numbers affected all start 2729..30. My wife's R171 was registered 2009 but built 2008 and has an engine number that starts 2729..31. The last six digits of her engine number are actually less than 468993 (considerably so - it starts with a 2!), but it is certainly not amongst those affected.
 
I disagree with your interpretation of that TSB. I believe that there are two separate issues:

  1. M272 Engines up to serial# 2729..30 468993 suffered from a material manufacturing fault affecting the the balance shaft sprocket; This component was (is?) produced from sintered steel and the sintering process had not been carried out correctly. This was corrected from that engine serial# onwards
  2. Separately M272 Engines up to serial# 2729..30 759427 can suffer a failure of the camshaft adjustment solenoids. It does not follow that there is an underlying problem with the balance shaft sprocket on engine serial#'s 468994 to 759427
It would appear that the dealer initially mis-diagnosed the problem, having also misinterpreted the TSB.


It it possible that this may be the case. However there was another TSB which I found on motortalk.de which has now been pulled. This had explicit instructions to the dealer not to commence any work on physical timing gear until the new "improved" solenoids were fitted and these had given the fault codes (ie ignore fault codes from original solenoid/sensors).

This aside, we can gather than from 30.. 468993 on the timing gear is allegedly made of stronger stuff. However this doesn't rule out the possibility of it still failing if the previous owner abused the vehicle or if it was subject to lots of driving that puts strain on the gear (eg many 100's of hours idling in heavy traffic). This noticeable wear may have been why the original technician assumed it was buggered.

Either way I will get a new solenoid/sensor tomorrow. I highly doubt it will cure the rocking/vibration of the engine at idle and other symptoms but I hope to be proved wrong.
 
However there was another TSB which I found on motortalk.de which has now been pulled. This had explicit instructions to the dealer not to commence any work on physical timing gear until the new "improved" solenoids were fitted and these had given the fault codes (ie ignore fault codes from original solenoid/sensors).
I remember reading that one. What I don't remember is the part numbers of the "more tolerant" sensors, so I can't tell if they are the same as the revised ones that are listed in the current TSB.
clk208 said:
This aside, we can gather than from 30.. 468993 on the timing gear is allegedly made of stronger stuff. However this doesn't rule out the possibility of it still failing...
Agreed, but I'd rate it as a very low probability.
clk208 said:
Either way I will get a new solenoid/sensor tomorrow. I highly doubt it will cure the rocking/vibration of the engine at idle and other symptoms but I hope to be proved wrong.
Erratic valve timing is likely to cause strange behaviour of the engine at idle, so I'd be interested to hear whether or not the replacement parts effect a cure.
 
If I were you I might even take the dodgy solenoids and pay at your own expense for the upgraded timing gear if you intend keeping this car a LONG time.
 
My W164 ML350 has this issue, the CEL has been on since February and it's done 133k miles. First thing to note is that the engine runs absolutely fine, starts OK and does the same MPG as it ever did. However, a CEL is now a MOT fail so it has to be addressed.

So yesterday I had the four Camshaft Timing Control Solenoids (£20 each and £60 to fit) replaced with the revised part as per the Mercedes bulletin and the CEL light went out.

For six minutes.

There may possibly be an issue with the Camshaft Position Sensors, but they are quite expensive to fit in the hope that changes things and the codes point to constant camshaft adjustment ergo it is almost certain the sprocket is worn.

There is a simple way to check this (which the dealer should do) - you need to remove the Camshaft Position Sensors and align the balancer (305°) to front cover pointer. Once done, you should see stamped numbers on the Impulse Wheels and they should align exactly with the holes. My didn't - they were adrift on the LH bank by a margin & this apparently is where the chain tension is, so it shows up there first.

An indy can do the repair for £1.6 to £2k - a dealer more like £4k - £5k as it's lots of hours labour.

My heap of junk is off to an auction next week so it becomes somebody else's problem:D
 
Thanks all for the replies. Will respond in detail in due course when I get a minute.

Back from an 800 mile road trip after having the new cam sensor fitted. 600 miles in to the trip the check engine light came back on and has stayed on since after several short journeys.

^bob your comment is interesting regarding there being no noticeable symptoms. The workshop manager test drove my car for a few miles and reported he thought the sprocket/gear was fine. Sounded a little like BS as I had heard there would be no serious symptoms until the gear is almost rounded off entirely.

I am bored of fighting them over this issue now and will ask MBUK to have it independently inspected.
 
It's a moot point as to what happens eventually - the Amercan forums ponder this and opinions range from it simply not starting to valves hitting pistons.

Mine has done some 10k miles since the light came on & the engine honestly seems fine (famous last words). If it wasn't for the fact that it would fail it's MOT, I might have been tempted to carry on to see what happens:p

Regardless, this shouldn't detract from the fact that the dealer has to sort this to your satisfaction so good luck with that.
 
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Just to close this off for anyone who was interested - apologies for not updating sooner:

They got the initial diagnosis of duff timing gear wrong initially was the verdict, which did tie in with the engine number being way after the affected batch. They changed a cam sensor which was leaking oil (this is reported to be the only issue on the revised engines). But 600 miles later the engine warning light was back.

So I went to a completely different dealer in a different group, acted dumb (this bit wasn't hard
smile.gif
) and got a full diagnosis again. The other cam sensor was leaking oil now. They changed it and 4000 miles later everything is still spot on with no signs of trouble so fingers crossed it is all sorted. I haven't heard of any reports of timing gear issues on the updated engine numbers so this is a good sign.

When I was in the second dealer for the second diagnosis they showed me some detailed printouts of how the timing was adjusting through the rpm range I think. Apparently this was all working fully to spec. This dealer had no reason to try to get out of any warranty work going either as the initial one may have done immedeately after purchase.

I was promised an additional 12 months of Tier 1 warranty for some problems I experienced and how this issue was handled. I still haven't got any paperwork for this yet but hopefully they will stick to their word.

So a happy ending I think.
 
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So, many months and many miles on and no issues mechanically with the car - everything has been pretty peachy. Couple of services at MB dealers in the meantime and nothing other than routine maintenance that springs to mind.

As it's coming up to June 2014 and the expiration of the 1 year extended warranty which the dealer told me they had added to the car I thought it would be an idea to get a couple of niggles which recently sprung up addressed (shrieking passenger window and burning rubber type smell from front tyre).

On phoning my local MB dealer it seems the extended warranty was never added to the car. The idiot I was dealing with at the original dealership who told me he had extended the warranty won't return my call.

I suppose a bit of a non-story in that nothing disastrous has happened where the warranty would have been really needed, but it pisses me off being told a load of BS, particularly as to get the "extended warranty" I had to drive to the dealership in question in Blackburn last Summer so they could carry out a STAR test before "renewing the warranty". I was on secondment in London for 3 months at the time and had to make a special trip up there. That's a day of annual leave and 500 miles which could have been far better spent.

Moral of the story - do not trust a word your friendly MB dealer says and get everything in writing immediately.
 
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This kind of behavior is not the preserve of MB. All dealers are the same to some degree or another, with very rare exception.

Good luck with the car.
 
Moral of the story - do not trust a word your friendly MB dealer says and get everything in writing immediately.

What is disappointing from your episode is that the quality of support post purchase gives little confidence in competency.

I bought my 2009 C280 last year perhaps with some naivity of the "superior" Mercedes engineering and customer support. As mine comes up for the first service since purchase I think I shall keep my fingers crossed that I do not have to add to some of the horror stories I read here!

PeterG
 

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