• The Forums are now open to new registrations, adverts are also being de-tuned.

W208 CLK 320 - Some engine issues

If your lumpy idle is really noticeable then I would guess your egr vale is playing up and not seating correctly. The only clue star will give is a high air intake temperature.
It won't log a fault code

I knever knew EGR valves were in these engines?! If it is, hopefully MB should recognise this fault.
 
I just went out for a quick drive to sort out my mothers TV so decided to capture my rev counter.

[YOUTUBE HD]2ii19e2VHwU[/YOUTUBE HD]
 
I just went out for a quick drive to sort out my mothers TV so decided to capture my rev counter.

<a href="http://www.youtube.com/watch?v=2ii19e2VHwU[/YOUTUBE HD]">YouTube Link</a>

I think there is an error in your link since its giving a validation error. What's the title of your video in YouTube. Thanks
 
The difference isnt so pronounced when warm, but there will always be a drop when dropped into D from N as the TC will have engaged drive and be offering a resistance.

My car doesnt vibrate or shake. You could almost stand a coin on its edge on the the engine without it falling. I say almost, as I have seen dieselman do this in his oil burner and the £1 coin just stood there.
 
Last edited:
The difference isnt so pronounced when warm, but there will always be a drop when dropped into D from N as the TC will have engaged drive and be offering a resistance.

My car doesnt vibrate or shake. You could almost stand a coin on its edge on the the engine without it falling. I say almost, as I have seen dieselman do this in his oil burner and the £1 coin just stood there.

Yes I see what you mean. In my car, vibration and shake are both present at idle :( I wouldn't even bother to put a coin on the bay tbh because I know it'll fall the next instant. When I put my hands on the engine bay, I can feel the movement of the engine from left to right so its definitely an issue that needs sorting.

I hope MB can give me the answer...
 
Getting the car diagnosed today @ MB Leicester. I hope the time and money will be worth it. I will update with their findings soon.
 
Got the car diagnosed from MB and it seems their 'initial diagnosis' was worth it.

The mechanic has reported that there is misfiring occurring in all (I can't remember if he said all or 4) cylinders. See picture attached

Cause: Plug leads are too small hence are stretching. The leads at the back 2 cylinders are very small. I have attached a picture of the STAR report of the misfiring codes.

He has mentioned that the plugs and coil packs are fine.

He has quoted a price in the region of 400-500 pounds for all 12 leads and Labour (with the provision of changing the coil packs if the new leads don't solve the problem). Leads are £25 each so totalling £300 for genuine Mb.

I'm disappointed that those new leads I got from GSF are not correct...any chance for me to ring GSF and take this issue further?

Since the cost is extremely high and I don't have any intentions to spend that kind of money for a 1998 model, I'm considering.contacting Bosch and get a quote for the leads since I can't find them on ECP or GSF.

MB said they can fit the leads (provided by me) @ £30 + VAT per hour (1hr job) or they can fit leads and coil packs @ £50 + VAT per hour ( max. 2hr job).

If I can find Bosch leads (since they are the closest match to genuine MB leads) I can consider getting then.installed at MB Leicester. Would you recommend to get coil packs changed at the same time also and if I should, I assume I should go for Bosch ones?

I have the original leads with me but I don't think its a good idea to re-fit those since the new plugs did not solve the misfiring - meaning that most-likely the original leads are faulty.

Please advise. Thanks
 
Last edited:
Its good that your now getting somewhere. You also need to ask your mechanic why he was not able to pull up these codes. I also find it strange that you had these and yet the MIL was not activated, can you check that the MIL comes on for a few seconds when you first turn the ignition on.

It looks like just cylinder 4 is playing up
 
Its good that your now getting somewhere. You also need to ask your mechanic why he was not able to pull up these codes. I also find it strange that you had these and yet the MIL was not activated, can you check that the MIL comes on for a few seconds when you first turn the ignition on.

It looks like just cylinder 4 is playing up

Yes I'm finally getting somewhere now and happy that I'm not wasting my time anymore.

What is a MIL? Is that Management Ignition Light by any chance? Is it the same light as the EML?

Hmm, the mechanic said a misfire is occuring in 4 cylinders and not just cylinder 4.


If only one cylinder was misfiring, would that cause a noticeable shake in the cabin?

Also, I thought a misfire is really loud/has bangs in the engine note but I haven't noticed those at all.
 
So today I rang Bosch to get the part number for the ignition leads and I thought I should share the info for other M112 engine owners.

There are 12 ignition leads total of which, 8 leads are slightly different to the other 4 leads.

The Bosch part number for the 8 ignition leads is 0356912948 and brochure code EE 948.


The Bosch part number for the remaining 4 ignition leads is 0356912950 and brochure code EE 950.

The EE948 lead is the smaller one and the EE950 being the bigger lead.

The original factory fitted leads removed from my car are also Bosch and have the MB symbol and same part numbers as above.

I have been quoted £122.21 inc VAT and delivery (12 leads) from TT Automotive (Loughborough). I'm still waiting for a quote from ECP.

I still can't figure out.how the aftermarket leads are short since their total length is 27cm - bigger than both genuine MB lead types.

I think its a good idea to get them changed all and make the most out of the 1hr labour charge...

I don't think GSF will be interested to talk about it...
 
Last edited:
your readout shows p0300 which is a multiple misfire, and a p0304 which is a misfire on pot 4. As the code shows damaging TWC I would have thought the MIL/EML would have been illuminating, that's why I asked if it comes on then goes out after a few seconds which is what it should do.
 
your readout shows p0300 which is a multiple misfire, and a p0304 which is a misfire on pot 4. As the code shows damaging TWC I would have thought the MIL/EML would have been illuminating, that's why I asked if it comes on then goes out after a few seconds which is what it should do.

I just popped in the car and had q quick check for the light. See attached picture. I didn't see the EML light when.putting the key into position 2. That's strange...
 
Last edited:
Dead bulb, or someone knew it (the engine not the bulb) had a fault and removed it before they sold it?
 
Last edited:
Dead bulb, or someone knew it (the engine not the bulb) had a fault and removed it before they sold it?

Yes it could be the cause. If someone has removed the bulb then it could all make sense. But even if the bulb had been removed, why did those MB specialist not manage to detect any misfire codes when it had.it'sst star check? Strange...
 

Users who are viewing this thread

Back
Top Bottom