Why didn't Mercedes-Benz fix an engine problem with the S Class?

During July 2012, my 2005 Mercedes-Benz CLS 350, purchased new from a UK dealer, went in to a Mercedes workshop to check why an engine warning light was on. It transpired that some of the timing mechanism was worn and this was replaced at a cost of £3000. In January 2013 the car was in the workshop again with the same problem. This time they replaced a worn balancer shaft at a cost of nearly £2000. Both these costs take into consideration a 75 per cent discount on parts. I am aware that the same problems have been experienced in Europe and the USA, and that the problem emanates from the selection of steel used to manufacture some of the parts fitted in M272 V6 engines between 2004 and 2006. I would have thought that Mercedes should have issued a product recall. I would be interest to know if any of your readers have suffered similar problems and what were the resolutions.

Asked on 20 July 2013 by DA, Derby

Answered by Honest John
Yes I did find previous examples of this in both the CLS and the W221 S Class entries in www.honestjohn.co.uk/carbycar. I'm surprised it occurred in the W221 S Class as this was not launched until 2006, by which time the issue should have been resolved. Another embarrassment for Mercedes-Benz in releasing a new engine before it was properly developed and tested.
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