2016 c class 28.000 miles now undriveable and unsellable what would you do ?

[Julieoscar]

Hi all I bought a used 2016 merc c class from a local merc dealer . It was two years old it had 15,000 miles on the clock good condition etc . After a matter of weeks the engine management light came on and the car wouldnt accelerate properly .Took it in, and the problem was cleared . a few months later had the engine fault again , had the nox sensor changed this was under warranty . A few months later same problem ,changed the other nox sensor .Then had the same problem a few months later this time I was told it could need two nox sensors changed together , or a temperature sensor or a new turbo . As it was getting more and more costly with no real answers I took it to a local merc garage the mechanic had the car for 4 weeks he changed lots of parts the fault light would clear and then when he drove it again it would reappear . Through a process of elimination he found it was the temperature sensor . That was changed and it worked really well for approx 4 months then the fault light came on again although not with the acceleration problems . Weve just put in another nox sensor which has cleared the fault but after a 5 minute drive the pick up was slow and the light came on again . the conclusion now is that when you accelerate oil is getting into the air and landing on the temp gauge which means it needs a new turbo . Both the independent garage and the mercedes garage think this could be a possible solution but arent 100% sure . In the meantime im left with a car that you cant drive on motorways etc as it has poor pick up , cant be sold as it has the engine management light on !
I could spend £4 or £5 k for a new turbo but would it work ???? I just wanted a few opinions and to know if anyone else has had similar problems . Im not very mechanical so could you keep any responses simple please . I dont know what to do for the best I dont know if I can spend £4k and be back to square one ,I dont have the money to spare and it would break my heart . What do you think ?

 

[onefortheroad]

Drive it onto a slipway and wait for the tide.

 

[DSK]

4k for a turbo?

I’d get it to a reputable independent MB specialist recommended from here.

Then get it fixed, whilst it’s working sell/trade it in for something else.


Sent from my iPhone using Tapatalk

 

[tpn]

Presume that you have checked that the oil level is correct, as in, not overfilled.

I believe in targeting the simpler and cheaper things first.

Family member had an MOT failure with her little Audi A1.

Garage pinpointed an oxygen sensor failure. Car had less than 10k miles up.
As there were discrepancies in the overall readings I advised her to go home and put at least 30% dipetane into the fuel and drive it for 20 miles.

She drove it 10 miles; emissions Zero.

Try Dipetane, it is magic.

 

[ioweddie]

Or a box of matches

 

[Noddy 99]

I was quoted £900 by an indie for a turbo on a W211. I didn't go ahead and the problem turned out to be something else.

BUT the point remains - £900 is a different ballgame to £4000...

 

[KennyN]

What temp sensor are we talking about , as i am sure there are a few on various different places around the engine and associated ancillaries ?

If your garage and Merc think it is the temp sensor , again , that is getting covered in oil then why are they not removing it and giving it a clean and seeing if the EML goes out , or replacing it ?

Does the suspect sensor give any false readings when being monitored "live" ?

Lots of variables on the initial post , but one thing that isn`t variable is the fact that i would be taking the car elsewhere as it seems that your mechanic and MB are having a "disco" with your invoices.

As stated . get the car to a recommended Independent MB specialist , knowing what part of the country you are from may help in recommending one.

K

 

[SL63 Mark]

As stated . get the car to a recommended Independent MB specialist , knowing what part of the country you are from may help in recommending one.

K

^^^^ This ^^^^

You need someone who understands these cars and has the right diagnostic tools.

Wherever you are taking it, they are happy to spend your money chasing the fault.

 

[Julieoscar]

Thanks everyone , the second garage is a reputable specialist and to be fair they haven't got a fixed price for the turbo the £4k price was from the mercedes dealership . If any of the issues made sense then I would go ahead and install a new turbo . The oil check is a good shout. it had the engine light on but was running fine for 4 months , ( i just ignored it as it had happening too many times ) took it in for B service engine light came back on shortly after picking it up and the over acceleration started again . Had the MOT come up so we had to get rid of the engine light ,for it to pass . Diagnostics said it was the nox sensor again. changed that that fault cleared drove it for three miles and as I put my foot down the light came back and the pick up went . ( never had this happen before ) the fault is now coming up as temp sensor ie its getting contaminated . Its just the fact that every fault seems to be different , I could just keep going on and on . The oil check sounds like a good place to start . Thanks again . Ps Mercedes also told me a lot of the issues are because its a diesel and I didnt drive it enough during lockdown

 

[Steve@Avantgarde]

Is this the Mercedes 651 engine or the Renault engine?

The fault could be different becuase the oil is contaminating different sensors and the techs are being blinded by the fault codes as consequential effect rather than looking for the cause. Are you noticing puffs of whitish smoke out the back on idle if you throttle hard?

I did have a C220 of 2016 vintage about 2 years ago which was failing its MOT emissions and a small puff of white smoke was seen on throttle. We did various KAT treatments to clean it, then went looking for the fault which included looking at injectors, engine sensors, compression tests until we just took the KAT off and it was black with a film of oil residue.

That turned out to the turbo. Looking at what we charged that customer, including all the diagnosis which amounted to days trying to figure it out we charged £2945 inc VAT. I think we managed to get a recon turbo from Universal for about £1500.

 

[Steve@Avantgarde]

Thanks everyone , the second garage is a reputable specialist and to be fair they haven't got a fixed price for the turbo the £4k price was from the mercedes dealership . If any of the issues made sense then I would go ahead and install a new turbo . The oil check is a good shout. it had the engine light on but was running fine for 4 months , ( i just ignored it as it had happening too many times ) took it in for B service engine light came back on shortly after picking it up and the over acceleration started again . Had the MOT come up so we had to get rid of the engine light ,for it to pass . Diagnostics said it was the nox sensor again. changed that that fault cleared drove it for three miles and as I put my foot down the light came back and the pick up went . ( never had this happen before ) the fault is now coming up as temp sensor ie its getting contaminated . Its just the fact that every fault seems to be different , I could just keep going on and on . The oil check sounds like a good place to start . Thanks again . Ps Mercedes also told me a lot of the issues are because its a diesel and I didnt drive it enough during lockdown

I can assure you that that is complete and utter bollocks.

 

[Rotorhead500]

Looking at the mileage you've covered (about 13k?) in 4+ years or so, do you generally do short journeys with it, or is it used infrequently, but for longer trips?

 

[Julieoscar]

Is this the Mercedes 651 engine or the Renault engine?

The fault could be different becuase the oil is contaminating different sensors and the techs are being blinded by the fault codes as consequential effect rather than looking for the cause. Are you noticing puffs of whitish smoke out the back on idle if you throttle hard?

I did have a C220 of 2016 vintage about 2 years ago which was failing its MOT emissions and a small puff of white smoke was seen on throttle. We did various KAT treatments to clean it, then went looking for the fault which included looking at injectors, engine sensors, compression tests until we just took the KAT off and it was black with a film of oil residue.

That turned out to the turbo. Looking at what we charged that customer, including all the diagnosis which amounted to days trying to figure it out we charged £2945 inc VAT. I think we managed to get a recon turbo from Universal for about £1500.

Thank you for this information its very useful , I'll go back to the garage and let them know