I have the same issue on my E55, for me im 90% sure its related to the crankcase breather hoses. Replaced plugs, wires and coils with no major improvement.

Specifically, I noticed the hose at the back of the throttle body was a little loose, pushed that in and my car was 80% less shaky - looking to replace the hoses soon.

If that specific part of the hose system seems solid, and no visible cracking in hoses I would do a smoke test to be sure.

Do you get a bit of idle chasing on cold start once fast idle begins to decrease at all?

 

Hey V8K, so I had a look and I'm not sure which hose exactly you mean, you say "Specifically, I noticed the hose at the back of the throttle body was a little loose", I do assume it's the one that plugs into the intake tubing? (Marked red) If it is, it's not super tight but also not cracked or falling off.

Or is it another one? I don't see many more here:

 

Very interesting. I'll go and check this out tomorrow and report back what it does for me! Thanks for responding
I'm still chasing this.

 

Hi Gripen, so that hose you highlighted in green actually connects to the bottom of the throttle body through various connections. Its difficult to see but if you feel around the bottom of the throttle body you will find a hose. Again, its difficult to see so you will have to feel around for it.

If you look at the image below, I believe it’s part 158 which is the bridge between breathers and throttle body that was the loose connection for me, hope thats a bit clearer.

 

Okay much clearer, thanks for the picture! I'll have a look and feel around there and report back this evening.

 

I just had a look and feel and indeed I found the hoses and number 158.
Something I noticed is that the breather hose, number 152 in your screenshot and highlighted green in my photo is really sandwhiched in. I can't move it at all. I wonder if the routing of 152 is correct, feels like it might not be that some mechanic who worked on it did it wrong. Do you know if yours is the same? Might be an idea to remove the throttlebody and have a look.

For the rest it seems quite tight on there?

 

btw. I have EPC but I can't find if there should be a gasket on the throttlebody, do you know if yours has this? Mine from what I can see on the outside almost looks like it doesn't have one.

 

mate that is really interesting. To be honest with you I think my car is actually missing that bracket that is holding your hose in place!!!

If you look at this video, at about 8:40, this guy pulls off a plate that he later says holds the hose in place, so I think your car was worked on correctly:

There will definitely be a gasket between the throttle body, you will be able to compare in that video, the guy also takes throttle body off which may be helpful for you.

If you do decide to take throttle body off, would really appreciate if you could send pictures of that metal plate, in case it has a part number on it as it looks like I will need to buy one.

I'll be working on my car tomorrow as I need to reseal one of my breather covers, will send some extra pics when I do so that you can compare.

It's possible that the issues causing the shaking are different for us, if I definitely am missing that plate. Do you have an OBD reader by any chance, you can look at MAP sensor pressure for example to narrow down if your shaking is down to an air pressure issue. For me, this is how I came to the conclusion that the vacuum lines were an issue as pressure was fluctuating more than it should. You can also check if any cylinders or running rich or lean - if MAP sensor looks find then could be an injector issue for example.

 

If there's any way you could get a clearer picture of the numbers on that plate, would be a big help for me

 

Did some digging and found the part number actually: A1121410240

For anyone else's benefit.

 

Hey V8K,

Oh yeah you probably really need that clip as it holds the breather hose in place it seems! Hope it will help you. I see you already found the part.


This afternoon I've mailed the local mb dealer and ordered all the breather hoses and gaskets from the dealer and can pick them up tomorrow morning, maybe better to just renew, probably won't hurt and it wasn't too expensive

A3059970345	SEAL RING ELECTRONIC GAS ACTUATOR
A1121411380	GASKET ELECTRONIC GAS ACTUATOR TO INTAKE MANIFOLD
A1120181882	Engine Crankcase Breather Hose
A1130100382	Engine Crankcase Breather Hose

It looks like most of the people remove the surge tanks and then the throttle body, I just hope I don't have to as I didn't order those gaskets and I do seem to read that it's necessary to replace them.


Thanks for the MAP pressure suggestion, I do have an obd reader and should be able to bring up the MAP pressure. I'll do this tomorrow morning and post the results!
Did you also have the same that it's only on cold start but if you were standing in D at a stop light that it's fine?

 

Hey Gripen,

I found a video of a guy taking the throttle body off without taking off surge tanks, may be helpful:

The only issue you may find is that there is a chance surge tanks will have to come off anyway to replace the breathers, this is something I was looking into as well.

Yes, my issue is the same where I get the vibrations while in park. In drive and reverse it smooths out almost entirely. While the car is cold, I do occasionally feel 'pulses' if I am stopped in traffic and the car is in drive but my foot is on the brake. This smooths up almost entirely when the car is warm though. I get a bit of idle chasing on cold start too, once it starts to settle just above 600rpm, but after that rpm doesn't really fluctuate.

Didn't end up re-sealing my breather today due to unpredictable weather, but got some pictures for you to compare to your car, as you'll be able to see I am definitely missing that bracket so will do both jobs once that part gets delivered.

Also found some oil residue in the hose that connects breather cover to airbox, presumably because the seal on the breather cover is not great at the moment, is weeping but not massively so far, but something that may be worth looking into on yours too.

Can also see what looks like a gasket between my throttle body connection, have to look quite hard though lol.

 

Hey V8K, very identical issue then indeed. It's almost like you are describing my issue I'm happy for you actually that it looks like the plate is missing as that could solve your issue partially perhaps?Thanks for all your photos and information so far it has helped a lot!

I went to the dealer yesterday to pick up all the parts I ordered but when I was there I also ordered the surge tank gaskets because I think you are correct that they need to come off to replace the breather hoses. They were not that expensive, like 11 euro per piece I believe and I will pick them up tomorrow.

I've also added a can of Liqui Moly Pro Line Fuel Injection Cleaner today. We'll see if that does anything to the injectors/fuel system...

Will probably do the replacement job tomorrow or Tuesday and I'll report back my results!

 

Thanks Gripen, good luck with the replacement job, hopefully we are closer to fixing this issue!

 

Hey V8K, so yesterday I went ahead and replaced some parts:

• Air filters
• Cabin filter
• Breather hoses
• Throttlebody gasket
• Surge tank gaskets

Some things I noticed:

• The old large breather hose was almost completely plugged on one side with smudge. The part that plugs into the bottom of the throttlebody was much longer on the new part than the old part, I think it was also an updated part number. The openings of the hoses were much enlarged on the old parts after so many years.
• The Fuel Pressure Dampener on the fuel rail looked quite bad from the outside. I know that doesn't say anything about the inner workings but I have made the decission to go ahead and order it and replace. I've also read it can cause these idle fluctuations: Question on fuel pressure regulator - MBWorld.org Forums
  
  
  
• I found a vacuum line, I think, that had a really damaged hose (marked this red line). I'm not sure where it goes to be honest....? Any idea? Think I'll try and replace this as well.

All went smooth until I got to the surge tank reinstallation where I snapped off one the bolts while I did use my torque wrench. I did manage to get it out luckily. So tomorrow I will order some new bolts at the dealer. It looked really tight so I went ahead and did a test drive anyway...

When I fired it up it was still shaking a littlebit. Maybe it has improved a little but I don't think it solved the issue. I will do some more driving after I get the snapped bolt installed again.
Will also have a look at the MAP sensor again, try and read it as you suggested earlier. Anyway, I'll update when I have more news. Did you manage to replace the parts?

 

The mb dealer couldn't supply/order a new fuel pressure damper. He even read the text that these are not made anymore and that the person ordering should source it somewhere else or have the existing one fixed. So I have just ordered a brand new one off ebay from Latvia and it wasn't cheap, that I can tell you.

The bolts and clamp I can get tomorrow. Will update once I get all parts (this can take a while from Latvia).

 

Hey Gripen,

That situation with the fuel pressure damper sounds frustrating, hope you managed to get that surge tank bolt out too.

I have some mixed but mostly positive news about the breather cover reseal, my car is shaking about 60% less now, still get some noticeable idle searching and shakiness for a little while on cold start and a bit of vibration when in park, but overall much better, absolutely zero shakiness when in drive and stopped in traffic now which is a major improvement. Overall, the car feels a little smoother, but let me tell you, this job was a massive pain in the ass.

I resealed both breathers, though in my case it was the larger one that was leaking, but I thought good practice to do both, majority of my time was spent cleaning the mating surface to reseal. I noticed that in the larger breather cover, there was a decent amount of oil pooled, did not think to get a picture in the moment but I think that explains why my hose consistently had oil residue in there. Basically on the larger cover (passenger side UK), you can also pour in engine oil, and there is a path that should be sealed with RTV (will send a picture of what I mean in future when I get a chance), I believe this seal must have also failed given how much oil was pooled in my breather area.

You mentioned that one of your breather hoses was gunked up with oil, would recommend opening up the breather cover to check if there is any oil pool present, its also possible that one of the holes that allows air to pass through may be partially blocked, they are extremely tiny and if your hose was gunked up there is a chance the air hole is too, which side was it out of curiosity?

I also added some hose clamps to the breather hoses as they were quite difficult to take off and I had to use some force, so in case I damaged them; still haven't got round to changing the hoses themselves.

I'm also still waiting on that bracket to be delivered, it's been almost 2 weeks! Hopefully that will also help but I am definitely a step closer to a smoother running car. I have only taken it on one drive so far, but the difference in idle and general smooth running of the engine was noticable.

Hope that helps mate.

 

Found a picture I took of the cover I mention above actually, you can see the path next to the oil fill area where RTV must also be laid, the oil fill area should be closed off from the rest of the breather area it seems:

 

Hey V8K, sounds like you've had a massive improvement anyway. Congrats on it!

The breather hose part that was full of gunk was indeed the one on the larger breather cover with the oil fill plug that you picture above. I have done the valve cover gaskets but the breathers didn't leak at that time and looked fine so I didn't do those. I think they were done previously... Am now considering doing them as well just to be sure I don't have the same as you and that I just know it's done correctly Who knows maybe mine is leaking as well. I did not see it done on any receipts I got with the car so might as well have a look.

I have ordered the sealant A003989982010
The 5 bolts seem to be 8.8 and look rather new so it must have been upgraded from alu to steel already. I'll update after I do this as well. just afraid it might take a bit more time as I'm waiting for parts........

It looks like the fuel damper still has not been sent from Latvia (sigh..) and might be delivered mid july. I did get the clamp from the dealer yesterday but they lost the surge tank bolt that I broke off so had to reorder. Had the whole parts department searching everywhere for two bolts Eventually I said guys, it might be cheaper to just reorder them and they agreed haha?

 

Thanks Gripen, yes definitely worth doing the breathers for peace of mind at the very least! Quite likely your bolts are the new stainless steel ones, my old aluminium bolts were torx head whereas the new ones are hex.

I will also look to purchase the fuel damper, looks like it is a serviceable part from the forum link you sent before and I did notice a bit of a fuel smell when I took the car for a spin today.

 

Yeah you are completely correct, they are the hex variant with 8.8! So I guess I don't HAVE to replace them. Just waiting on the sealant now.

In the meantime some stuff has happened regarding the fuel pressure dampener. The expensive OE Mercedes damper from Latvia was cancelled. I think they found a buyer who wanted to pay more so said they made an error and they didn't have it anymore so it was cancelled. At the same time I did find another forum thread and a facebook group post where the guys couldn't order one either and used another fuel pressure dampener which was only 30 euro off of Amazon if you get the Bosch part

MB: A1110780292 / Bosch: 0280161511

MBUK forum post: MB CL 55 AMG Kompressor Fuel Damper/regulator leak - fixed. A1120780092 swap with A1110780292 | Engine
Facebook post: fb post

Let me be very clear, I don't knowif they are the same spec wise or if this is a really bad idea but they said it worked great. I did order it and just received the package and installed it. The car runs the same I would say...................... so it doesn't look like it helped much. I'm not sure if the car needs to adapt or anything. Probably not and I just wasted 30 euros

I want to test it again cold tomorrow and see how it behaves and I'll report back.

 

Car behaved the same with the new damper.
What I have done is a compression test just to be sure (had never done one) and the results are ok/good I think:
Cyl 1: 152
Cyl 2: 155
Cyl 3: 162
Cyl 4: 157

Cyl 5: 155
Cyl 6: 152
Cyl 7: 165
Cyl 8: 167

So the engine seems at least healthy to me.

After that I built everything back together and did two things:

• TCU relearn/reset
• Idle relearn/reset

Honestly, after the reset it seems 95% fixed in P, it was completely smooth. I think the idle is also a tad higher (50/75/100 rpm?).
V8K, I'd try this if you haven't already.
First 2 resets...

 

Congrats mate, sounds like you're basically in the clear!

Annoyingly, I'm still waiting for that bracket to be delivered, but got an update from the postal service today that its on its way.

I did actually do the throttle body reset a while ago with no luck, but that was before I resealed my breather cover which made a big difference in itself.

Once I've installed the bracket hopefully this week, I will do these resets and report back.

 

The TCU reset is a myth unless done with the MB SDS computer.

 

Hi Gripen,

Hope your car is still running smoothly since your last update.

I've only just found the time to change some more parts (the bracket I was waiting on made no difference) and was hoping you could help me locate where exactly one of the parts you mentioned you replaced goes:

A3059970345

SEAL RING ELECTRONIC GAS ACTUATOR

its a green o-ring, and from diagrams I've seen online I'm not sure exactly where it would go, is it in the y-pipe that is connected to the airbox?

appreciate the help.

 

Hey V8K, sorry I was on Holiday with my other car...
The green SEAL RING I couldn't figure out what it was for as I didn't see any such ring when I removed the throttle body. Maybe it's for normal M113, I'm not sure. I have not used it

Car is still running a lot better but there is still a slight vibration which is kind of annoying but I can live with it.