Alan Sakoman

Hi all,
2016 E63 AMG-S 4WD.

Have a Eurocharged tune on it - we tried a couple of maps and still happening even without it so I know it's not the tune.

I changed the spark plugs to 2 step colder twice now.
NGK 97506 "2-Step Colder" Spark Plug - 8-Pack (8 Cylinder Vehicles) from burgertuning

Dealer also did the torque checks etc.. since the dang things is so senstive.

Replaced 3 coils - those dang things snap so easily on 1, 3, 5...

Here is the issue - vehicle runs awesome normally, accelerates, no hesitation no misfires. perfect.
Floor it, hits 6-7+ K RPM starts misfiring like crazy and continues to misfire - have to pull off, turn the car off and back on and then it's back in business NO PROBLEM..

I can't figure out wth is going on - potentially:
fuel delivery??? but why wouldn't it stop misfiring when let of the gas?
timing ???

Any ideas are welcome.

PeterUbers

These misfires - do they happen on stock ecu?

what gas brand/type are you using

how long have you had the tune?

Adnan Siddiqui

Just to completely knock it out of the board, I'd replace rest of the coils as well. I had a similar issue and 5, and 6 were acting up. Replaced 7 and had to run out for something and car misfired, did the last one and since then thankfully no misfires.

Issue was similar where 2-3 runs car would be normal and as soon as it went on the 3rd or 4th run past 5k it misfired.
Highly recommend doing all coils sir

Alan Sakoman

Hey there,
I only use Shell 92 .. once in a great while I'll do BP.

I've had the tune for almost 2 years now.. again car runs great, accelerates great, even when I push it hard with pedal shifting (so it's not the revs) .
I even think Launch works - I have to check that again.

I don't remember but I think this happened to be me on stock.. We also backed down the tune about 10% at one point.
this tune is on a lot of E63s (at least Jerry mentioned that) and no problem..

When I floor it though - man it just starts knocking like a banshee ... turn it off , turn it back on and like nothing happened

Alan Sakoman

Thanks Adnan - that was going to be my next step -- they are fairly cheap $55/pop - I might just get a whole set and replace it.
Wanted to see what other ideas people might have..

PeterUbers

Could be the winter blend of fuel -- add about 10% of E85 or 30% 100octane in the tank and see what happens after 20 minutes of allowing it to mix

did replacing the coils help on the misfiring cylinders?

SAMzE63s

What did you gap them at? thats the real question

Alan Sakoman

.22

Alan Sakoman

Every time I do some "servicing" it seems to help for a while.. this is why I'm a bit confused...
I also have weird codes on a few things (see my other post if you care to see what they are)- wondering if I have an electrical problem somewhere..

chassis

Do you have oil in the electrical harness? Pull off the connectors from:

cam pos sensors (4)
cam magnets (4)
ecu (1 or 2)
o2 sensors (2 or 4)

Oil in the harness can lead to misfire. Root cause is fail-to-seal at cam pos sensors and/or cam magnets.

Alan Sakoman

UPDATE: checked all plugs, - ECU, O2, Every Fuel injector, every coil , cam pos, cam mag - all dry as a bone.


Hi Chassis,
Good call out on those but I changed all 4 cam pos sensors a couple of months ago - top connectors were dry the lower ones had a little bit of oil but I sucked it all out.
The magnets we replaced by the dealership under warranty 2 years ago (why they didn't replace cam pos is a very long story of dealership being a french word for shower.

I'll check ECU connectors and o2- good call. That should be quick

chassis

If oil got into the harness, and the ECU is not (yet) contaminated, the most reliable fix is to replace the wiring harness. There is likely no way to remove all of the oil from the harness, once it gets in there.

Alan Sakoman

stupid question - would octane boosters achieve the same thing as mixing 91 and 100?

cls5504matic

I would go back to stock tune for a while and let everything learn again. then get her tuned. Have u tried just the latest model MB spark plugs? I've also heard you can swap all coils from the left bank to the right bank. You don't have to change the coils for torn boots, they sell them separately but I would consider doing all new coils. Are there any codes?

Alan Sakoman

Yea regular CEL Code P301 , P300 -- misfire on Cylinder 1 ..
I checked all the coils today - didn't see any torn boots.. I changed the coils on 1 3 5 already...

My plan of attack is:
1) Try higher octane (Per PeterUbers)
2) Replace coils (Per Adnan and you) / maybe plugs too - just to check - especially since they probably got fouled up by misfires (I'm using the NGK 97506 at .022)
3) go back to the stock tune , say screw it and probably sell the car as it's just troublesome in many areas unlike my 2011.. really disappointed in this series

nota_amg

just for confirmation, when you say you replaced the coil, do you mean the coil itself, the replaceable "boot" or both(I'm assuming just the boot, by your post?)?

I don't see where you say a specific cylinder is misfiring. If just one cylinder is misfiring, swap the coil/boot from the cylinder that is misfiring with the coil next to it, see if it follows the coil/boot.

If you are getting misfires on multiple cylinders, more than likely you got some bad gas. You can pull the fuel pump/level assemblies out under the rear seat to get a look at what the fuel looks like, but be careful, they are tricky to remove from the tank, especially the Passenger/Pump side. You can just remove the white caps and move the assemblies to the side a little in the tank to be able to get a hose in there and siphon out all the fuel.

Good luck

Alan Sakoman

No I replaced the actual ignition coils on 1 and 5 not just the boot. - it cost me >$577 at the dealership ( I know I know )
It also looks like they installed the newer "version" - 276-906-05-01

The cylinder misfires always starts with 1 and then 5..

Can you tell me more about this fuel pump/level assemblies and the purpose of that step?
In the original post - the car drives fine normally -it's the rolling start, flooring, 6K+ RPM where it starts misfiring like crazy. - the rapid fire sounds ..prrrrrr
Turn off/turn back on - good to go!

nota_amg

First: Cyl 1 and 5 are the front two cylinders on either side. swap Cyl 1's coil/boot with Cyl 2's, and Cyl 5's with Cyl 6's. then drive and see if it follows either coil. If it does, replace the coil and/or boot. If not, continue diag...

If you have bad fuel: pull out the rear seat bottom cushion and pad, there are 2 metal circular "doors" with 3 10mm head bolts holding them in along with some foam sealant. remove the bolts and peel off the covers to expose the 2 rings that secure the fuel pump(right) and fuel level/filter(left). you can remove the rings and open the fuel tank to siphon out the bad fuel(if that is the case).


Cylinders are laid out as below:

[Rear of car]
4 8
3 7
2 6
1 5
[Front of car]

cls5504matic

If it is front cylinders you may want to borescope them and check for scoring and the valves. I’ll link to a relevant thread.

PeterUbers

https://mbworld.org/forums/w212-amg/...ml#post8073603

BiturboSF

Yes but in my opinion, I would stay clear of octane boosters as they all contain MMT. It is the orange deposits that will foul out your spark plugs & clog your cats. You can google it. If it were me, I would just spend a few more bucks for a couple gallons of 100 octane or just use a bit of E85

cls5504matic

this thread might be pertinent: https://mbworld.org/forums/gl-class-...re-solved.html

JAYCL600

once it gets in good, youre ****ed...I had oil wick into my fuel injector harnesses. Its such a cluster ****, will throw no codes and will drive you batty!!

PeterUbers

never use this snake oil

kenneyd

Holy crap! That's got to be the scariest threat I've ever read