2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault

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Wed 27 Apr 2022 09:24
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

I have owned this car for 17 years and it is in fantastic condition. I have two files of invoices to prove it!

Always serviced and repaired at Mercedes dealerships, in fact the service book is full of stamps. For the last ten years I have had the car in northern Italy. No problem getting it repaired or sourcing parts which usually came from Rome.

Now it is back in the UK it has developed a misfire or hesitation when pulling away, especially on a hill. The rest of the time it seems fine. Initially the car was suffering from a power loss. The MAF sensor was changed and it ran perfectly for a while, but then the engine warning light came on.

I took the car to my local Mercedes dealership on the south coast, and they were unable to do anything with the car, because they no longer have the STAR diagnostic equipment for a 2001 CLK. The service manager apologised, but basically just sent me on my way. Clearly they do not want to be bothered with older cars, even if they are in top condition.

So now I am at a loss what to do. If Mercedes can’t repair a Mercedes, what is the point of ever buying one again?

Edited by Speedbird 747 on 27/04/2022 at 09:26

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Wed 27 Apr 2022 09:32
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

In case anyone can help here, so far the fuel and air filters have been changed, along with the MAF and MAP sensors.

Apparently there is some oil in the wiring harness, which is a known problem as these cars get above 80,000 miles. An independent garage has suggested taking off the fuel rail and investigating the oil breather.

Anyone have any other ideas please? There are O2 sensors either side of the catalytic converter. Is it possible one of those could be faulty?

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Wed 27 Apr 2022 10:24
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - elekie&a/c doctor
Oil in the engine wiring harness is very common on these . It starts from the cam variators at the front of the engine and migrates down to both the lambda sensors . You need to get the conectors to the lambda sensors and engine ecu checked for any oil contamination. You certainly don’t need MB star diagnostic to fix one of these .

Edited by elekie&a/c doctor on 27/04/2022 at 10:25

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Wed 27 Apr 2022 10:46
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

Many thanks for your reply.

The car is going into an independent garage on Friday. Do you think the oil migrating might be the problem?

How do you stop the oil from contaminating the lambda sensors?

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Wed 27 Apr 2022 11:16
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - elekie&a/c doctor
Oil in the lambda sensors can cause running issues . If oil is evident, then it’s virtually Impossible to get it out of the harness. A new loom would be needed . However, to reduce the problem, there are 2 small extension harness links that connect to the cam variators , this will stop the migration. Available from MB dealer parts . Last time I bought a pair , they were about £65 for the 2 .
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Wed 27 Apr 2022 13:27
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747
Oil in the lambda sensors can cause running issues . If oil is evident, then it’s virtually Impossible to get it out of the harness. A new loom would be needed . However, to reduce the problem, there are 2 small extension harness links that connect to the cam variators , this will stop the migration. Available from MB dealer parts . Last time I bought a pair , they were about £65 for the 2 .

Many thanks for that.

What if the loom needs changing?

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Wed 27 Apr 2022 16:00
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - elekie&a/c doctor
May still be able to buy a loom from MB , but don’t hold your breath .
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Thu 28 Apr 2022 12:00
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - focussed

This company in the UK can make you a new loom if not available from Mercedes.

www.autosparks.co.uk/#

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Thu 28 Apr 2022 12:17
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Gibbo_Wirral

Is it worth asking round the MB forums to see if anyone local has the clone Star diagnostics kit?

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Thu 28 Apr 2022 13:38
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Metropolis.
I would try your nearest unofficial Mercedes specialist, they are more used to handling the older cars, often they are former dealership mechanics that trained in that era!

I agree it is appalling that they dont support the older models. I understand they are not really obligated and prefer selling a new car to you, but if the cars are as good quality as the marketing would have us believe, long term ownership should be celebrated and supported. They have potentially lost a future sale.
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Fri 29 Apr 2022 21:24
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Big John

Now it is back in the UK it has developed a misfire or hesitation when pulling away, especially on a hill. The rest of the time it seems fine.

With the car moving back from a warmer climate to the cold/damp climate in the UK could this be a ignition coil pack type issue? It's the " misfire or hesitation when pulling away, especially on a hill" that makes me wonder - this sounds like my car a few years ago when it suffered partial coil pack failure(replacement cured the problem). Does it feel as though it's dropping a cylinder or two?

Also was the MAF sensor replacement an original equipment item or an ebay cheapie? It obviously ran well for a while.

Edited by Big John on 29/04/2022 at 22:10

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Tue 3 May 2022 03:54
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

It's an AC Delco MAF which cost £95.

I might change that for a Bosch one.

It doesn’t feel like it is dropping a cylinder or two once it gets going. I had a three hour drive last night, and once warmed up it dove really well. I have mentioned your experience to my independent garage and the car is booked in again for next week.

Many thanks

Edited by Speedbird 747 on 03/05/2022 at 13:23

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Wed 4 May 2022 11:47
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

I have a just had a long chat with a lady from the Mercedes EU headquarters. It was an Amsterdam number.

Basically it appears that Mercedes are no longer prepared to support older cars with parts or diagnostic equipment in the UK. Currently I am in France and I am going to try here for the parts I need, as the French don’t change their cars so often and Mercedes have an older fleet to maintain in the country.

I never had any trouble getting parts in Italy or having problems diagnosed there until July last year. The dealership had the diagnostic equipment in Treviso, and parts came from Rome.

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Mon 16 May 2022 20:58
2001 CLK W208 Cabriolet 200 Kompressor - Mercedes dealer unable to diagnose fault - Speedbird 747

So after the AC Delco MAF sensor was installed, it ran OK for a while.

Then it started hunting especially when cold, misfiring, a nightmare at junctions or roundabouts. MAP and O2 sensor forward of cat also changed. Manifold off looking for oil contamination, 2 hours labour.

Anyway I suggested that the MAF might be faulty. Got a Hella one today. All fine now.

What a palava. Just added up all the bills on this car since I bought it 16 years ago. Total came to £16,857. That is taking it to Mercedes dealerships exclusively for you. No wonder you can pick up these cars so cheap.

Rubbish quality cars and over engineered.

Edited by Speedbird 747 on 16/05/2022 at 21:00

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