Black smoke from exhausts

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Iamxpod

New Member
Joined
Aug 16, 2020
Messages
13
Location
Suffolk
Car
E250 avant garde 2.2
Hi guys, I'm still new to owning a mercedes e250 cdi 2012 avant-garde and to this forum so please bear with me as far as etiquette required.

I need some help please

I picked up my used mercedes from a dealer on 13 August and within a couple of weeks noticed black smoke bellowing from exhausts when under hard acceleration and a vibration from front brakes when coming to a slow stop. The eco stop wasn't working and the battery was only at 18%(now fixed with new battery)

The garage had the car back in on Wednesday this week and said they couldn't find any faults on diagnostics but did a carbon clean on the engine and changed brake pads(no issues found on rolllers)

I picked the car up on Friday 11th but it was late when they called me, so said they would leave keys out as they wouldn't be there When I collected it. As soon as I left the garage I discovered the brakes still vibrating when stopping and it is still got black smoke when under hard acceleration. Does anyone have any idea what this could be? The back of the car is covered in black soot.

Mileage is 75k and had oil and air filters changed before I collected it.

Any help is appreciated . Thanks Mark
 
Brakes sound like warped discs - garage should sort, insist they come for a drive with you so you can demonstrate
Black smoke is unburnt fuel - could be a number of things - injectors, MAF, EGR - needs some proper diagnosis and garage should sort.
You have 6 months warranty if bought from a garage.
 
Vibration under braking could be a suspension issue rather than brakes, black smoke could be a DPF issue- what warranty came with the car-seems hard to believe these faults were not apparent to the dealer before sale.
 
He took it for a drive with me and agreed the brakes feel odd his initial thought was abs problem. But said can't find any thing wrong in roller test And changed pads as goodwill gesture. Would any of the other faults egr maf etc show up on a diagnostic from an indi garage or would it need mercedes to do it? Thanks again
 
Vibration under braking could be a suspension issue rather than brakes, black smoke could be a DPF issue- what warranty came with the car-seems hard to believe these faults were not apparent to the dealer before sale.
They gave me a 3 month warranty, which is with them as they also have a garage,incidently they also did the mot, which failed on rear coil spring which they replaced
 
You could try a few really hard stops (not to a complete stop, just down to 10mph) from 60-70 mph to try and clear any pad deposits from the discs.
 
Brakes sound like warped discs - garage should sort, insist they come for a drive with you so you can demonstrate
Black smoke is unburnt fuel - could be a number of things - injectors, MAF, EGR - needs some proper diagnosis and garage should sort.
You have 6 months warranty if bought from a garage.
So just took it to a friends garage and no problems shown on diagnostics the only strange thing was it shows only 2 dpf regens over the life of the car and one of those was today. Will take back to garage Monday and hopefully they can get to bottom of the Black smoke. BTW the smoke smells a bit oily??
 
If it smells oily have you checked the engine oil level? It could simply be a case of over filled...check the dipstick if you have one.

I'm not clued up on your engine, but assuming it has a PCV valve, check it's functioning otherwise it would be introducing oil into the inlet.

When you say diagnostics were done, was this using Star?

Vibrating brakes in my experience have been down to warped discs and the remedy is to replace them, new pads on warped discs won't sort the issu, the garage is just trying cheap fixes.

Under consumer law you can legally refuse to accept the car if they can't sort your issues out to a satisfactory standard.
 
If it smells oily have you checked the engine oil level? It could simply be a case of over filled...check the dipstick if you have one.

I'm not clued up on your engine, but assuming it has a PCV valve, check it's functioning otherwise it would be introducing oil into the inlet.

When you say diagnostics were done, was this using Star?

Vibrating brakes in my experience have been down to warped discs and the remedy is to replace them, new pads on warped discs won't sort the issu, the garage is just trying cheap fixes.

Under consumer law you can legally refuse to accept the car if they can't sort your issues out to a satisfactory standard.
Hi thanks for reply appreciated. It was using a lucas system.
 
Thanks for all the help with regard to the Black smoke, garage have arranged for main dealer to have a look and see if they can do a diagnostic to find out why its doing it, so fingers crossed. As far as the vibrating when braking, if the discs where warped would it do it at speed as well as when slowly braking? I think it also makes the grinding/vibrating noise if I just coast to a stop without braking, but is definitely more noticable when braking slowly,....any ideas anyone please. Again thanks for all the advice
 
Black smoke is unburnt fuel - could be a number of things - injectors, MAF, EGR - needs some proper diagnosis and garage should sort.
.

or poor driving technique.....with a diesel....
 
Welcome to the fold.

The warranty is largely irrelevant; it won't cover wear and tear, and the warranty company are likely at best to pay only for repairs that clearly aren't wear and tear, and only essential repairs at that. Good engineering practice usually doesn't come into it; if one hydraulic engine mounting is shot, for example, and the other one on its last legs, but hasn't actually failed, they'll pay only to replace the failed one.

It is the vendor that is liable for repairs, so the warranty really protects only him, not you. Your rights are under the Consumer Rights Act 2015, and to avoid liability for repairs the onus is on the vendor to prove that any faults that occur within the first six months of your ownership were not present or developing when the car was sold.

If the garage has arranged to take the car to a main dealer to have diagnostics done, that's a good sign; you're just over the thirty day period when you could have returned the car and insisted on a refund, and if they were a bunch of complete crooks they'd probably not have done that.

Let us know how you get on.
 
Welcome to the fold.

The warranty is largely irrelevant; it won't cover wear and tear, and the warranty company are likely at best to pay only for repairs that clearly aren't wear and tear, and only essential repairs at that. Good engineering practice usually doesn't come into it; if one hydraulic engine mounting is shot, for example, and the other one on its last legs, but hasn't actually failed, they'll pay only to replace the failed one.

It is the vendor that is liable for repairs, so the warranty really protects only him, not you. Your rights are under the Consumer Rights Act 2015, and to avoid liability for repairs the onus is on the vendor to prove that any faults that occur within the first six months of your ownership were not present or developing when the car was sold.

If the garage has arranged to take the car to a main dealer to have diagnostics done, that's a good sign; you're just over the thirty day period when you could have returned the car and insisted on a refund, and if they were a bunch of complete crooks they'd probably not have done that.

Let us know how you get on.
Thank you, they have said that if MB main dealer can't sort the faults with the smoke and vibrating that they will take car back still which is a relief....although will obviously have to see what happens when I do try to return, but so far they have already put a new battery in and put new pads on, so thought it worth sticking with it especially as MB diagnostics/inspection should hopefully show up any other issues as well. Well keep you posted and thanks again for welcome and advise.
 
Thought I'd post an update finally So....mercedes after having the car for 2 day found a sensor not working and 2 minor oil leaks however they couldn't find what was causing the Black smoke. They tried to force a DPF regeneration but it wouldn't work. Gave me the car back in limp mode? The garage i brought it from wanted to do a DPF manual clean but i decided as the problem wasn't found and loss of faith in the car that i would return the car to the dealer. I have received a full refund.
Thanks for all your help with this.
 
Despite the outcome with the car, clearly a very good garage that didn’t try and play the difficult game.
 

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