[Mutandegrande]

My car is actually a lease that will be going back in the next few weeks as my new car is due to arrive shortly. I suspect therefore, my car will be on the used market pretty soon. Depending on your view of this cylinder head issue, mine could be a good used buy as it's already been fixed, or a lemon given it has gone wrong..... If anyone is in the market for a used A35 exec in white I'm happy to share the number plate (to seek out or avoid!) subject to any forum rules.

 

[GemmaDA35]

Recently bought this car from motor point Glasgow. Couple of weeks ago. My husband got it remapped for me stage 1 , Miltex Down pipe & decated . Car was on the dino at 380hp. Anyways we have ran this car for a number of weeks with this soft wear Etc with no issues. We notice a strong smell of petrol started inside the car. Then the engine management light came on Orange! We had it plugged in and came up it had misfired somewhere but hadn’t lost power Etc while doing so. We manage to plug it in again with right codes the engine light came off. Only for it to be on again the next day. We took it back to the tuning place to have it bk standard ( software removed to then plug it back in again. Was coming up fault with cat Etc as obviously there’s no cat there. So light off again today back to retune. For it to then come on again with strong smell of fuel. Been trying to read all these pages to try and find the problem. The car has standard motor point warranty but not merc. Obviously we know everything will need put back standard afore the car can go bk under their warranty. Has anyone had this problem ? Could it be fuel injectors ? cylinder head ? Cars still only at 18k but seen on here can do less and still have these problem !!
Help a lady out guys a love ma wee A35 and she’s rather poorly at the min ☺

 

[veeeight]

Not saying this is what it is - but - Read through this

AMG A35 - New Cylinder Head Please

Hi all, I'm new to the Mercedes A Class community but have a little story for you all. I recently purchased a 6 month old AMG A35 from a main dealer. Had a few months and have loved it up until last weekend when engine light came on. Called Merc who sent out technician. Diagnosed coil pack and...

www.aclassclub.co.uk

 

[Forrester]

It is most likely to be what is in that thread unfortunately.

 

[Forrester]

Recently bought this car from motor point Glasgow. Couple of weeks ago. My husband got it remapped for me stage 1 , Miltex Down pipe & decated . Car was on the dino at 380hp. Anyways we have ran this car for a number of weeks with this soft wear Etc with no issues. We notice a strong smell of petrol started inside the car. Then the engine management light came on Orange! We had it plugged in and came up it had misfired somewhere but hadn’t lost power Etc while doing so. We manage to plug it in again with right codes the engine light came off. Only for it to be on again the next day. We took it back to the tuning place to have it bk standard ( software removed to then plug it back in again. Was coming up fault with cat Etc as obviously there’s no cat there. So light off again today back to retune. For it to then come on again with strong smell of fuel. Been trying to read all these pages to try and find the problem. The car has standard motor point warranty but not merc. Obviously we know everything will need put back standard afore the car can go bk under their warranty. Has anyone had this problem ? Could it be fuel injectors ? cylinder head ? Cars still only at 18k but seen on here can do less and still have these problem !!
Help a lady out guys a love ma wee A35 and she’s rather poorly at the min ☺ View attachment 10452

Please do let us know what happens. Good luck.

 

[beta2004]

Hello everyone,

I had a question about my a35 amg 2019 model (44k km's),

Its been at mercedes for almost a week now for a diagnose which still hasn't been done, does anyone have any idea how long that might be before they do?

I first took my car to the garage where I bought it, and it turned out that 1 of the cylinders needed to be replaced, but they took it to mercedes just to be sure...

Does anyone have any idea how long I will be without my car?

 

[beta2004]

How long did it take for you all to fix this issue? Because 2 weeks ago i also had this issue but still no answer by the mercedes dealer,… they still didn’t do a diagnose,… its annoying me called already 2 times with same reply “we don’t know when”…. Can anyone help me out all i know that C2 needs to be replaced

 

[Forrester]

How long did it take for you all to fix this issue? Because 2 weeks ago i also had this issue but still no answer by the mercedes dealer,… they still didn’t do a diagnose,… its annoying me called already 2 times with same reply “we don’t know when”…. Can anyone help me out all i know that C2 needs to be replaced

Many have experienced the same treatment as you, although it does seem better now in the UK. It seems to depend on how much experience your market has had with the issue. You need to persevere, unfortunately.

 

[alexcannas]

How long did it take for you all to fix this issue? Because 2 weeks ago i also had this issue but still no answer by the mercedes dealer,… they still didn’t do a diagnose,… its annoying me called already 2 times with same reply “we don’t know when”…. Can anyone help me out all i know that C2 needs to be replaced

I wouldn't be surprised if they kept the car for 4 to 6 weeks to get this done. There is a wait time to get parts and then the repair is a big task. So you have to also wait for resources to be available to get the job done.

So as Forrester said be patient. It took me eventually 3 months from the day I noticed the problem to getting it fixed.

 

[BlackAnt]

There are some who got theirs fix in a reasonable time as below

Update - fault occurred 21 October, cylinder head replaced and completed 11 November. 3 weeks in total. Have copy invoice detailing work carried out over 3 pages. A few issues along the way but had a nice hire car and they are repatriating my vehicle 120miles by lorry this Monday coming. I am interested in seeing if I can get an extension to my warranty with such intrusive work done on a engine only 18 months. I guess you would hope that it will all be fine but I am concerned that another fault related may occur down the road. I will let you know how I get on unless other have tried?

I've finally had news that mine has been fixed and is on the way back from the dealer closest to where it broke down. The issue happened on the 30th Oct, part arrived on the 9th Nov.

 

[Forrester]

There are some who got theirs fix in a reasonable time as below

It seems to be luck of the draw. Also some dealerships seem to be more pro active than others. So for my coolant sensor and centre console warranty work I've been waiting several weeks for the parts to come in. They'll probably arrive in the new year when I'm on holiday.

 

[EthanH]

Hello everyone. This is a really useful thread so I thought I’d share my recent experience (horror show) in the hope others find it useful for those out of warranty.

I bought a 2019 A35 with 29k on the clock Jan this year. Recently developed misfire (symptoms included reduced power/rough idling etc - all of which mentioned above). Booked in at Merc Basingstoke - tech diagnosed low compression in cylinder 1, 2 AND 3 including valve guide disintegration. Recommended new cylinder head.

I was 3 months out of standard manufacturer warranty. Quoted £6500 by Mercedes, out of good will and some gentle persuasion Mercedes UK agreed to cover 75% of the cost. Engine seemed to be running as it should - was taking it easy as if running in again. Tech admitted the grade of alloy used for original cylinder head in W177 was lower grade (and admitted he’d replaced at least 3 heads already so possibly more issues than posted on here. Ran on Premium unleaded as I always do.

Roll on this morning…..

The car had to be recovered at the roadside this morning. Full loss of power, engine light on, had to limp to nearest lay by to await recovery - showing the exact same misfire symptoms. No prior warning. Car now in awaiting further diagnostics. Gutted is an understatement.

I’ve saved the worst to the last……my
courtesy is an A200d…

Has anyone else had issues following replacing of a cylinder head?

 

[alexcannas]

Mine was replaced a month ago and is all good atm. Is not an easy job to do as you are essentially rebuilding the engine, so they may have gotten something wrong in the rebuild. The branch I took it at Stevenage asked for extra days to test both hot and cold start performance, so were very careful.

 

[Forrester]

Good point 👏👏👏

Okay both. I'll move it across to the main thread rather than delete, as everyone with this problem wants to be heard.

 

[Chow Gar]

Update, first start up yesterday and everything seems great, carried out another compression test and all cylinders are reading 235psi which is good news. Let her warm up to optimum temperature and took her out for a spin, again everything seems fine. Put it this way before I decided to take on this repair myself the engine was all over the place it literally looked like it wanted to jump out of the car due to the miss fire, and now you can’t even tell the engine is running when stationary. When collecting my injector seals from merc I spoke to a MB engineer and he was saying that the a35 that have been through there workshop with the same faults have all more a less had sticking exhaust valves ? Therefore my a35 will be having a engine oil and filter change every 5k miles and it won’t be having that watery 0W-20 Mercedes’ engine oil. I’ll post my costs later on once worked out just to show how possible this could be for some people with the same issues.

thanks

I think that you might be on to something here with regards to the engine oil viscosity used by main dealer servicing. As someone with a long standing trust issue with main dealers, I opted to have my 12.5K miles, Sept 2019 registered A35 only serviced at my friends Porsche garage and I have only used Castrol Edge 5W30 M, which is designed for Mercedes engines. Fortunately my car is still running well, with regards to the engine.

Early Porsche 997 cars also suffered a similar issue to this, but with cylinder bore scoring and after hundreds of them being rebuilt, many of the pioneering Porsche specialists, including Hartech in the west country, recommended that a higher viscosity oil should be used in these engines.

 

[Craig70]

I think that you might be on to something here with regards to the engine oil viscosity used by main dealer servicing. As someone with a long standing trust issue with main dealers, I opted to have my 12.5K miles, Sept 2019 registered A35 only serviced at my friends Porsche garage and I have only used Castrol Edge 5W30 M, which is designed for Mercedes engines. Fortunately my car is still running well, with regards to the engine.

Early Porsche 997 cars also suffered a similar issue to this, but with cylinder bore scoring and after hundreds of them being rebuilt, many of the pioneering Porsche specialists, including Hartech in the west country, recommended that a higher viscosity oil should be used in these engines.

It's not a high enough percentage of failure to be an oil issue.

 

[alexcannas]

Is also the location and nature of the failure... I don't see a connection between the exhaust valves and their sits on the head with the oil... Is not an area that is lubricated.

Note that MB added the following information in mid-2021 for the cylinder head removal/replacement procedure: The tightening of the cylinder head bolts offsets a slight distortion of the cylinder head in the longitudinal or transverse direction.

This leads me to think that they must have identified the culprit as the fabrication tolerances of the cylinder head rather than anything else.

 

[bixandjulia]

Hi all, this has been a valuable thread. I am having a similar experience. Bought AMG A35 sedan new in December 2020. Love the car and only has 21,000 kilometres on it but 6 weeks ago the engine light came on and I felt a loss of power. Mercedes dealer said cylinder problems as discussed in this forum and also said it was common for the car. Am still waiting for parts to arrive but was wondering whether people had any problems once the replacement cylinders etc were put in. I noticed a post in this thread saying maybe the original alloy was sub par. I hope the repair isn’t just a Band-Aid fix. I welcome responses.

 

[cosmos35]

Hi All,

In Canada, we are now getting a 15 year cylinder head warranty on M260 engines or 241k KMS for useful life. All models with M260 engines sold up to 2022 will be covered. I'd check with your dealer in your region to see if it's the same. Should definitely make long term ownership for these little cars more worth while. Hope that helps!

 

[bixandjulia]

Thanks for the response I will definitely ask the dealer for extended warranty on the cylinder heads. Nice to have some anecdotal evidence to support my request.