Knock Sensor needs replacing exhaust - quoted £1200!!!! :(

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E350Matty

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My E350 coupe 2013/2014 engine light came on recently and Mercedes said it needs the knock sensor x 2 replacing.

Quoted £1200!!!! I googled the part and it comes up really cheap so not sure why they charging me this.

Anyone else had any issues with a knock sensor. My mileage is 65,000.

Have to call them back to give them a yes or no answer on the repair.

Any advice would be great. Thank you so much :)


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What’s the labour aspect of the job?
 
Post title now says solved, so I’m probably wasting my time here...but anyhoo...a knock sensor is going to be bolted to the block, near the top so it can sense the detonations. On a V engine, they are usually in the V itself, so likely there are a LOT of parts that need to come off to get to them, meaning a lot of labour as well as gaskets, seals and fluids.

Interested to know the ‘solution’ though.
 
A couple of hours. 2 maybe 3 hours max I’ve been told.


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And the hourly rate?

MB have to be £150+ a hour nowadays, that could be almost half of the amount with the usual VAT etc depending on the exact figures involved.

Are the parts you priced up genuine? As obviously MB wouldn’t be quoting for non-original parts.

Query it with MB but I’m guessing they would have priced the job off book times using genuine parts - you can always ask an indi for a quote, who should be cheaper for the labour rate at least :)
 
Not sure how to remove the SOLVED bit of the post sorry.

Genuine Mercedes , I’m upset that this has an issue. Mercedes said £400 each knock sensor and labour on top. Did call another specialist and they quoted £350 each sensor and then labour on top which was around £900. Which is £300 cheaper.

Just spent a fortune on service , tyres , and brakes and this , the timing of Xmas and a January Tax return coming up. If I left this u TIL Feb would this cause any damage ?

Would give me more time to shop around and time to save up.

Thanks for these fast replies guys. Need to get back to Merc today with an answer.




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I’ve called around and a garage has quoted me £433 this includes VAT. For a knock sensor replacement. Garage claims there is only the one sensor.

Mercedes quoted me £1200. This is two knock sensors.

I’m really confused on the prices difference. I’m also waiting to hear back from Halfords Auto.




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Where are you located?
 
I’ve called around and a garage has quoted me £433 this includes VAT. For a knock sensor replacement. Garage claims there is only the one sensor.

Mercedes quoted me £1200. This is two knock sensors.

I’m really confused on the prices difference. I’m also waiting to hear back from Halfords Auto.




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there are two 'NOX' sensors (which I think is what you mean). They are around £325+ vat genuine and about an hours labour for each one. If you have been quoted £900 at a indi then that is a good price. You can probably get the sensors aftermarket but they may not last that long. Merc's are very sensitive to sensors! The issue you will have with non-genuine is you are unlikely to get a warranty on the labour so if they do fail, you will find yourself having to pay for the job twice.

Ive just searched 'knock' sensors and they are super cheap. I think you may have misheard them and actually it is 'NOX' sensors they are talking about as they are not only a common issue but the price then tally's up.

Natacha
 
there are two 'NOX' sensors (which I think is what you mean). They are around £325+ vat genuine and about an hours labour for each one. If you have been quoted £900 at a indi then that is a good price. You can probably get the sensors aftermarket but they may not last that long. Merc's are very sensitive to sensors! The issue you will have with non-genuine is you are unlikely to get a warranty on the labour so if they do fail, you will find yourself having to pay for the job twice.

Ive just searched 'knock' sensors and they are super cheap. I think you may have misheard them and actually it is 'NOX' sensors they are talking about as they are not only a common issue but the price then tally's up.

Natacha

Your totally right it’s the NOX sensors. I missed heard on the phone I do apologise.

Merc had no attempt to repair the issue. I was told that the error said replace both Nox sensor. Which I don’t believe so I demanded the error code and was told they don’t have it. Said I won’t leave until I have this code, eventually got the code P2201E1. I’ve done some research and it seems this problem often comes up often :( heard people getting them replaced and still getting an engine light on that points to a nox sensor error.

Im little pissed off because I don’t feel like anyone is being honest but shouldn’t be as it’s the first error in 5 years of ownership.

Feel so sorry for people who have loads of problems one after the other.





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Your totally right it’s the NOX sensors. I missed heard on the phone I do apologise.

Merc had no attempt to repair the issue. I was told that the error said replace both Nox sensor. Which I don’t believe so I demanded the error code and was told they don’t have it. Said I won’t leave until I have this code, eventually got the code P2201E1. I’ve done some research and it seems this problem often comes up often :( heard people getting them replaced and still getting an engine light on that points to a nox sensor error.

Im little pissed off because I don’t feel like anyone is being honest but shouldn’t be as it’s the first error in 5 years of ownership.

Feel so sorry for people who have loads of problems one after the other.


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Your annoyed that MB didnt repair the fault at a cost of c£1200 without your prior approval?....


Not that it helps you but this is quite a common problem - ive heard that the hot summer caused several failures...i had to have mine replaced back in the summer at a similiar cost.
 
Quite often after replacing them you will need a software update too. About 50% need both sensors and an update.
 
I have to agree with Pete above ^ . Having spent some time reading up all about NOX Sensors, what they do, and many other threads on different Forums where owners are replacing NOX sensors faster than tyres and at £400-00 each ....and two needed ....plus a session on Star then ..... it is a joke. Mercedes must be buying these in like Smarties and grinning every time two are needed.
I hope there will be plenty of 211's left to see me out my days, or till there is a permanent ban on diesels.

Anyway, back to the problem in hand. O/P asks if the sensor replacement can be postponed, from yet another NOX thread. Jay ( jaymanek ) says no.! (wise man ) otherwise you might block the DPF ........and how much is another one of those going to cost !. Start postponing Christmas 2019.

If I left this u TIL Feb would this cause any damage ?
NOX sensor confusion - Bluetec
Don't wait too long otherwise the dpf will block.

Steve
 
To be fair whether it’s NOX sensors, or turbos/glow plugs/injectors/EGR faults/fuel pumps/DPFs etc modern diesels are a nightmare when they go wrong. Over complicated, unreliable and expensive to repair IMHO, which is a shame.

Can you not get a warranty that covers these on a car of that age/mileage.

Hate to say it but £1200 buys a lot of petrol for the non-diesel models around.
 
A 4 year old diesel car with 65000 miles on it throws its owner a £1200 curve ball because we had a hot summer and this is a 'common' failure ?

You couldn't make this $hit up.

Someone remind me how much a new E 350 cost in 2014 ?

It was even worse! When we first started seeing them go wrong, the sensors were £550+ vat each, £1320 just for the sensors! Then they started failing too and a new part number/modified part was brought out and now they are thankfully, much cheaper although still eye watering.
too add to Toolmans comment, no I wouldn't leave them. It can and will eventually block the DPF and then you are in even more trouble.
Natacha
 
I hope when you demanded the code or your wouldnt leave that you stamped your foot, crossed your arms and made an angry face. I dont think this would pass the attitude test in getting any help from them.
 
A 4 year old diesel car with 65000 miles on it throws its owner a £1200 curve ball because we had a hot summer and this is a 'common' failure ?
Out of interest, what happens with this model in warmer climbs?

A "hot summer" in the UK is no worse than a normal summer in Spain (for example), but unless I'm told otherwise I assume MB still sell the same diesel models there.
 
Thank you guys for all your posts. I’m gonna use all the info I’ve gathered from this forum and others then contact Mercedes HQ. I will explain the Nox sensors are poor quality and are a common problem and it’s not right that I should be forking out £1200. Others have had it done as a good Will gesture out of warranty.

I will just give it a try as my last resort. Would be happy if they contributed some of the cost.

I bought the car new and have always used merc service depart.

You don’t ask you don’t get. Wish me luck [emoji37]


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Make sure you get an E class with a proper engine next time!

Having run V8s for 10 years in total, that kind of bill is alien to me.

:D
 

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