No problem and thanks for your inputs. I'm sure I've dumped a lot of info to sift through. I'm doing so in the hope that something will spark in other people's mind besides what I've been staring at. More thoughts/ideas are always welcome.

BTW, the injector and high pressure fuel pump noise is present. That noise is little more rapid with similar amplitudes giving the characteristic dieseling noise. My ticking/tapping noise is louder above the fuel system noise and quite distinct.

 

@Zerocarpileup
OP did you ever figure this one out? I found a few other threads in the W212 AMG forum with reports of the same sound. One of them, the OP found scoring in cylinder 5. Have you bore scoped any of the cylinders to check for that?

@tadiguy
My E63 makes the same noise. I have 66k miles on mine. Tuned. I recently did a Blackstone analysis and all the numbers came back good. No codes, no misfires, pulls hard. Same as for the OP, did you do a compression test and borescrope?

ETA: I just noticed something with this sound. Only can hear it when the vehicle is in R or D. It goes away when it's in P or N.

 

No resolution yet. Car has done a few more interstate trips and pulls like new other than noise. I don't know if any of the previous owners put a tune on it - not sure I can tell other than going to dealer for stock re-flash.
See a listing of my observations in my earlier post for info about cylinder pressure, leak down test, bore scoping etc. I don't think any of them are related to the noise.
BTW - my noise is there in all gears; it actually gets a little better in D and R.
If you ever find any clues please share.

 

[QUOTE=CZ 75;8798126]@Zerocarpileup
OP did you ever figure this one out? I found a few other threads in the W212 AMG forum with reports of the same sound. One of them, the OP found scoring in cylinder 5. Have you bore scoped any of the cylinders to check for that?


So after about 8 months of ticking the sound has completely disappeared on its own. Its been about a month and it hasn't returned. Literally the only thing i can recall doing out of the ordinary was doing a vacuumed oil change from the dipstick rather than a basic plug removal. Someone at Mercedes told me i could have created a vacuum and hydro-locked one of the hydraulic valves which stopped it from compressing and making excessive contact with the camshaft lobes. This is of course speculation. We discussed valve draining procedures that i have done previously in some range rover/BMW motors where you rev the motor for a while at different rpm in order to drain the valves. So i guess its still a mystery but i wont be doing anymore oil changes from the dipstick again.

 

[QUOTE=Zerocarpileup;8802422]Very interesting indeed...
Sucking oil out of the dipstick is standard operating procedure for MB and other German autos so I can't imagine that being a problem. In my case, I replaced all the lifters and rocker arms with brand new and it didn't make a difference.

Did you may be filled the oil level higher than you normally do? I've noticed that my noise seems to be dependent on the level of oil; it's louder when oil is low. In general my noise at idle has improved quite a bit but it still ticks under the slightest acceleration. It virtually disappears when coasting.

 

I have over 127k miles on my 2014 E63 and I have had the ticking/knocking noise for 15k miles. I have changed the oil multiple times with LiquiMoly 5w40 and use the LiquiMoly Ceratec additive ever since I had the car. I even tried a thicker oil 20w50 and the noise is still there. I eventually replaced the lifters of which 6 were bad. I did all the seals, gaskets and timing guides and the noise is still there. The car is tuned to 700HP with down pipes, intakes and still runs hard with no issues. I was told by a mechanic that when you tune these engines to the edge or performance and get bad gas, it causes piston shrinkage, resulting in the noise. The thing is, it happens to engines that are not tuned from what I am reading. I am also still investigating the issue and will post any updates.

 

Came across this video. Rocker arm failure can make noise also. I changed the lifters but no the rockers.

 

l’ve changed both rocker arms and lifters on the entire bank with no difference in the noise

 

Ok, so back to the drawing board. I will do a deeper dive into the noise. I have three mechanics looking into this. Funny thing with mine, when I run hard the noise stops for a bit. When I cold start it is not there.

 

Tyring to solve the same noise on my GL 450. Saw this on another forum. See link below: The sound sounds similar. Any chance this could be related to the tensioner interacting with a bad a/c compressor?

https://www.benzworld.org/threads/kn...shake.3065178/

The guy bypassed his compressor with a shorter belt and the knocking went away. Had to replace his compressor. Any chance this is the mysterious cause of the knocking?

 

In my case I'm sure the noise is coming from inside the engine. My noise is from the right bank and the AC compressor is mounted low below the left bank.

 

Hello all, I own a 2014 e63 S and have been SCOURING for a solve to this sound... I think I may have made a correlation... hear me out as I don't know this motor/trans too well. LOTS of people including myself default to engine internals. But NOTHING is a difinitive solve. I began to move towards the transmission/drive system after I noticed the sound was most pronounced while "in gear." Then, someone, somewhere mentioned the dual mass flywheel... this intrigued me. Could the sound be outside of the motor itself? Potentially even bad motor mounts?
Then, in this thread, the sound went away after a mightyvac oil change...

My question is: could it be the flywheel???
Again, I can't believe this is so mysterious and unsolved. Thoughts?

 

It could be depending on the car. That possibility has come up a few times during my research. Although the GL has a simple flex plate (not dual mass flywheel), I chased down the potential of this being transmission-related noise given that the noise is prominent under even the slightest acceleration and disappears during coasting or gear shifts. I experimented with shifting into neutral while driving and feathering the gas pedal a little bit to see if the noise will disappear and it did not. It could very well be transmission related but for me the correlation with low oil level is too strong to rule this out as engine problem.

 

I found this discussion to be really interesting. I have an M157 (no ticking/ no extraneous noises) AND an M278 (a very very VERY subtle "tick" (left side) at operating temps (42k miles) BTW, I've always had this subtle "tick"; I remember hearing this when my M278 was under 20k miles. I use 0W-40 with BG additive (Mobile 1) and vacuum the oil from the dip stick. No Xentry codes; no engine efficiency/performance compromised; achieving 28mpg/highway (sea level); pulls like a train. Frankly, guys, I have to listen for the subtle tick; wondering if it's just the injectors "spitting" precise fuel.

 

Have you guy's tried checking the gap and the health of the crankshaft bearing's on m157/m278 engines to solve the knocking noise?

 

The noise is coming from the high pressure fuel pumps on the right side of the engine in the back by the firewall. These Ride on the camshaft. What happens is that the lifter tappet it wears down and gets too much tolerance and starts tapping over time.


M157

 

I thought that too after seeing a youtube vid of someone showing how the rockers go bad. I replaced both HPFPs and rockers and I'm still getting it. I currently suspect the vacuum pump. My stethoscope points to that. I replaced the plastic check valve (it was destroyed) but seems like there's something metal internal that's loose causing the rhythmic, yet varying tick sound.
Does anyone have a vacuum pump they could giggle around or open up haha?

LD

 

I have still been loosing sleep over this! Haha! Every time I drive my car, I hear the sound and drives me maaaaad!

I'm beginning to think it's the Vacuum Pump. I just replaced the check valve which was destroyed but the sound still remains. My stethoscope confirms a tick is coming from there. Anyone familiar with the mechanics of the vacuum pump and when it "activates/works"? I noticed after start up and waiting a bit, as I select reverse and roll down the driveway, it starts to tick. Haven't noticed poor braking performance, BUT have noticed squealing brake pads even though they are still good. Haven't driven another w212 to compared pedal feel either though. Sorry to ramble, hoping we can solve this so anything could help!

LD

 

Hi, did you (or anyone else) get anywhere with this noise issue? Am hoping so…..
Thanks

 

Wasn't the vacuum pump. Mechanic thinks lifter or aux oil pump. Bring it in on 3/7 will report back. I just want a non ticking car!

 

Thanks, very interested to hear how it goes!

 

Possible Causes

1. PCV System Issues
   • The Positive Crankcase Ventilation (PCV) system is known to cause oil consumption problems in these engines. If the PCV valves or separators are clogged or malfunctioning, they can allow excess oil vapor into the intake.
   • Check: Inspect and clean/replace the PCV valves and oil separators.
2. Valve Stem Seals
   • These engines are known for weak valve stem seals, especially at higher mileage. Worn seals allow oil to seep into the combustion chamber and burn off.
   • Check: A borescope inspection of the intake/exhaust valves could reveal excessive oil deposits. A cold start smoke test can also help.
3. Turbocharger Oil Seals
   • The M157 twin-turbo setup has oil-fed turbos, and worn turbo seals can allow oil to enter the intake or exhaust.
   • Check: Remove the charge pipes and look for excessive oil pooling. If the turbos have shaft play, they may need servicing.
4. Cylinder Wall Wash-down (Unlikely in Your Case)
   • Some M157 engines suffer from oil consumption due to fuel dilution washing down the cylinder walls, but your compression numbers look healthy.

Next Steps

• PCV System & Valve Stem Seals: These are the most common causes. Start with a PCV check, then consider valve stem seals if the issue persists.
• Turbo Inspection: If the PCV checks out, inspect the turbos for oil leakage.
• Oil Change Experiment: Try a different oil (e.g., Mobil 1 0W-40 or 5W-50) and see if consumption changes.

 

Hi all,
having the same issue.
much worse in cold, during summer it's not that bad and goes away much quicker.
mine is also accompanied with rpm hunting(sometimes) after cold start when rpm goes down i get random spikes of 30-50 rpm, like engine can't find it's rhythm.
once hot and especially after a hoon everything works perfect like a clock.
thought I'd join the discussion and add my few cents if that at all helps.

I already changed PCV system and vacuum pump valve, plugs look good and are changed every 15k, oil every 3-4k.
Garage I trust say it's most likely piston slap, hence when warms up it goes away fully. It still bothers me, these first 20-30 minutes of drive with the noise feel like I'm braking the car.

I'm also very surprised how many people have encountered this noise and noone has a solution. I have 2 other friends with M157s that have this, doesn't make it normal though and we are all just going crazy over it.

I have a question though, could it really be something to di with exhaust maybe, do people with Catted exhaust also have it?

I think I'll ask to borescope the engine and compression test to face my worse fear. I had this noise last 30k miles and its all fine, car drinks 1L of oil per 1500ish miles

Fun and super annoying observation:
my normal consumption is as about 1L per 1500.
I changed my PCV valves and vacuum lines, plugs, coils - managed to do 3000miles and only added 300ml of oil - idle issue also went away !
1 of the coils failed (MB sent 1 old stock old style) - after replacing this to new style too - back to 1L per 1500miles and idle issue is present sometimes too.


I think I'll ask the guys to do compression test, smoke test and borescope to just face my fears of the worst.

If only it always worked as it does when warmed up fully..

 

Any luck?

 

Can't say I've seen the rev hunting you mention on mine, did you gap the plugs when you installed new ones? From what i have read .026 or .028" is optimal and improves idle- havent done it myself yet though but intend to.

Mine is bone stock (unless previous owner tuned it) and still has Cats and makes the noise, have had the car a couple of years now and got a bit worried the other day as it made that noise when hot as well, never had it do that before, it was always while warming up.

Why did you replace the PCV valves, did you have an issue? Mine uses a bit of oil but haven't really paid attention to how much, haven't been concerned, just figured i drive it hard sometimes and its to be expected?

Agreed this seems to be a very common noise and frustrating there's no solution. And I guess I'm praying its not bore score, was my biggest fear when purchasing the car. I'm the same as you, time to boro it and comp test when i get some time and go from there .....