Mercedes emissions recall

A reader has been sent a recall notice for his C-Class, but he's concerned that the software fix could dent his car's performance...

Used Mercedes-Benz C-Class estate

I own a 59-plate Mercedes C250 CDI and I’ve received a letter from Mercedes informing me that it is due for some work as part of a recall. It's for an engine management tweak that will, apparently, make the car Euro 5 compliant. 

While that's a useful thing, my car is no powerhouse and I’m worried that in optimising emissions there will be some tangible difference in its performance if I have the work done. 

However, I’m also wondering if it might make the car more 'sellable' in the future if it is Euro 5 compliant as that may mean it’s not eligible for low emission zone fees.

I’m also curious as to whether it would it help or hinder fuel economy, and are there any legal ramifications if an owner doesn't get recall work done to a car?

I’d be grateful for your advice on this. 

Nicholas Pope

What Car? says…

Mercedes UK launched a voluntary recall for several hundred thousand diesel models in 2017 to perform a software update that would reduce nitrogen oxide emissions. We believe this is the reason for your car's recall notice.

Used Audi A4 vs BMW 3 Series vs Mercedes C-Class vs Citroen DS5

According to Mercedes, the software upgrade is being carried out by dealerships when customers visit for a service or other maintenance work and will take around an hour. Although Mercedes has said that it doesn’t expect the upgrade to have any effect on the performance of the vehicles there are some reports online from C-Class owners saying their cars had a noticeable dip in performance after having the emissions fix done. 

The fact that there aren’t many owners complaining about this does suggest the effect isn’t substantial. However, this is not a safety recall so you don’t have to have the work done and there won’t be any legal consequences from not getting the car fixed. In the future, the DVSA may alter MOT rules to make it an automatic failure of the test if a car hasn’t had safety recall work done, but as this is a voluntary recall it shouldn’t affect your car. 

If you take your car to a Mercedes dealership for a service or other maintenance work, you will need to inform them that you don’t want the fix done as it will be carried out automatically otherwise. 

We don’t believe the value of your car will be affected if you don’t get the recall work done, and at present only Euro 6 cars are exempt from paying ultra-low emission zone fees, so having the fix done won't change this. 

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