Mercedes say that a new injector system for C Class and E Class diesels with the OM651 engine have now been fixed.
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So extensive was the problem that many owners were waiting months for their cars to be fixed as Mercedes struggled with a mounting pile of broken cars and injectors that were failing.
Mercedes tell us that the problem was fixed with the release of new injectors later in 2010, but Cars UK readers have continued to complain about their cars needing multiple visits to dealers with injectors failing multiple times (that original story garnered more than 500 comments from disgruntled Mercedes owners).
So it seems that original fix in 2010 is still causing problems, with our readers still reporting failed injectors, so we’ve asked Mercedes for an update on the progress they’ve made with the injector problems.
Mercedes say that although they believe the 2010 fix solved the vast majority of injector problems, a new injector system has been fitted to Mercedes C and E Class cars with the OM651 engine since the start of 2012, and has now released a quality update to replace the injector system in any earlier cars that are still having problems.
The updated injector system will be fitted to customer cars on the next service if needed, but if anyone is still having problems they can contact their local Mercedes Benz dealers to get this addressed sooner.
We’re pleased to see Mercedes has finally got a handle on this issue.



alex scotland says
i thought the merc brand was quality i think i will try vw
Nick says
My June 2012 C220 CDI with 29,000 miles is in for an new engine due to a Piezo injector failure which caused a piston to melt. The car has been with Mercedes for two months.!
francisco silva says
I’m from Portugal
and mine is in the same situation.
How was your case resolved?
Mark Deg says
I am thinking of getting a 2012/3 C220. Does anybody know if they are also prone to the injector problem? I mean I understand that they may fail but only after a decent amount of miles (150K+).
thanks
Mohsin says
C220 CDI SE 09 reg broke down completely today and is currently with the garage for diagnosis but doesn’t look good. Decided to do some research and reading all the articles and comments I remembered being called by my MB dealer 18 months ago saying there was a recall on a part but not specifying which one. I had it booked in twice but MB cancelled both times saying the parts were out of stock and in the end we forgot about it and we never got a call back. Anyway today, the engine light was on and the car suddenly wouldn’t go above 30mph and the fuel efficiency was down at 15mpg. Then when I tried to restart the engine was making a rattling noise and the car wouldn’t respond. In fact the engine would start, I could move a few feet but then it would shut down. Seems pretty bad but I wonder if it does turn out to be the injectors, do I have any rights with MB? I bought in 2010 and the car is registered in Oct 09. I had it serviced by MB in 2011 and 2012 and privately serviced in 2013. Thanks for help/advice.
Yconnolly says
I have a 58 plate c220cdi that has had problems since I bought it 12 months ago. Finally after being told the reason my car was doing 10 mpg at times was because i was using cheap fuel.(.texaco and BP may have something to say about that )the fuel pump has been replaced . The problem however remains… Could it be fuel injectors are the problem?
Veejay Sharma says
Thanks for this information. I am in the process of buying an E250 CDI BE and I am now changing my mind.
Roslyn Raina says
Does anyone know how Mercedes Benz have “fixed” the injector problems on C&E Class 220/250 CDI Blue Efficiency models. What type of injectors are currently used on the latest model of these cars ie are they solenoid or piezo and who supplies these injectors. If the injectors are solenoid type then the fuel consumption claimed on their brochure can not be true and higher level of soot in the emissions will clog up the diesel particulate filter much sooner. The piezo injectors which are highly accurate and precise is what has enabled such low fuel consumption and cleaner combustion. I recently test drove the c250 cdi be and was very impressed with the car but all the horror stories makes me very disappointed and undecided whether I buy one or not. I note that the new generation E class about to be released will offer the 250 cdi be engine but I am not sure whether it is exactly the same engine on the current model C class.
Craig Llewellyn-Bromage says
I have a C220 diesel sport. The MB roadside mechanic has just come out and diagnosed an injector problem. Identical symptoms to what has been described in this thread. It’s a 59 plate, I’ve have it a couple of years now and the warranty has just expired. I think given this information I’ll be expecting not to pay for the fix and will be looking for them to provide a hire car if it’s any longer than a couple of days.
Cars UK says
We would expect Mercedes to sort this despite your warranty position. They told us recently that they have “…now released a quality update to replace the injector system in any earlier cars that are still having problems.” (story link)
Clare says
I’ve bought a 220 c class diesel, 3 months old and this problem has just occurred … If I knew antything about this history I would not have purchased. Does anyone know my rights? I’m so annoyed that I want them to take it back and cancel my lease
Nick says
I have hadvtge sane issuevwith a C220 CDI 2012 with 29000 miles. This is a known problem with the Piezo injectors and Mercedes should be replacing them when the car is in for servicing (that’s the theory). In my case the fault destroyed my engine. After a 2 month battle Mercedes are replacing the engine under warranty. If you don’t get joy from Mercedes talk to Motor codes ( car industry regulator) for advice.
shiraz bhaiji says
My C220 CDI BE 59 plate broke down on 05/10/12 two weeks after the warranty expired. Mobilo attended and confirmed problem with injectors. Car carted to a dealer and given a hire c180 auto. Expected the car to be in for 3 to 5 days, turned out to be nearly 3 weeks as there were problems coding the new injectors with the new ECU. Car been back for nearly two weeks, it does not feel the same as before, engine sounds a bit louder, more of a lag between 2nd and 3rd auto gear and power seems a bit less. Luckily they seem to be sorting out of warranty cars with OM651 injector problems at present.
I am a little concerned to see if this fix will be for good and whether my confidence will return to in my car and the merc brand and whether they will sort any future problems with these injectors in the same way as they have with the old?
Bthian says
I have a 2010 E220 CDI here in Melbourne, Australia which has had the same injector problems but was earlier charged A$$800.00 by Merc Service for alleged fuel contamination saying they had to remove the contaminated diesel & cleaned up the fuel line plus a new fuel filter but the problem didnt go away the next morning and I took it back. Initially they asked me to drive the car for the next 2 weeks saying it’s normal to have lingering problem with it until the fuel sysrem cleans itself out (although they never said any such thing before)! I pressed the matter & they conceded the the injector was not replaced in the last service despite of me reporting the problems when I took the car in for routine service. It has been in the workshop now for 5 days and I’m told they’d now replaced the fuel injector, test ran it (including the service adviser driving it home last night “in order to make sure it didnt fault again”) and it’s now OK for me to pickup this afternoon. My fingers are crossed and hoping they will refund my A$800.00 and that there will be no more issue with the fuel system!
This leaves a bad taste in my mouth as Mercedes should have been up front & honest about the problem likes all other major car makers and it should have been a world wide re-call instead of waiting for each car to fail before being forced to replace the defective injectors. Anyone for a class action here?
shiraz bhaiji says
I certainly know how you feel. If your car still had the old type injectors, then they should have changed all four injectors, installed a new fuel return pipe and changed the injector ECU and programmed each injector to the new ECU. Contaminated fuel? if that was the case then their clean up should have resolved it. I certainly would insist on a refund and ensure all of the above work has been done as per instructions of MB. Let us know how you get on.
Ian says
Just picked my 2009 C25CDi BE up from having this done. I bought the car 2 months ago, was offered a free winter health check 2 weeks ago and they notified me it needed this replacement under warranty. The parts arrived in a couple of days and today they did the work. I wasn’t having any problems with the car so I’m pretty happy with the service from MB. The only slight disappointment is that it wasn’t flagged prior to me purchasing the vehicle (from an MB dealer).
MK says
Did you buy your car from an Approved Mercedes Used car dealer or some where else. Would MB fix the issue if the car was bought from an independent dealer like Car Giant?
Thanks
shiraz bhaiji says
Hi, I did buy my 59 plate used from an independent dealer and there were no issues with MB fixing the injectors out of warranty and Mobilo covers you for the first four years regardless of change in owner. Ask MB if there is a “recall” outstanding on the injectors on their computer records for your car. You might also find that there may be one for the power steering to be adjusted too. Both should be free if needed.