Very first contribution and already coming with issues

To quickly introduce myself, I'm a very happy owner of a S212 E63S 2014 used as daily.
I know that engine cam sensors have oil leakages and that they were replaced under warranty (I guess with the electrical wiring).

I discovered just before winter, that the car is equipped with an auxiliary heater.
It seems that since I'm using it (automatically heating engine and inside at morning time), I'm encountering :
1. "misfire on cylinder 2"
2. engine (oil) temperature probe communication issue.

It's very hard for me to establish a link between the issue and the activation of the auxiliary heater 'webasto' except if.... (reason of my post, is it coherent/possible or pure science fiction ?

One scenario could be
-> if when they replaced the wiring harness, some of the wires where not fixed at the expected place
AND
-> if these wires are exposed to the heat of the auxiliary heater exhaust pipe
? Could it be the root issue and trigger something like "false contact" or overheating wire propagating heat to the ECU ?

Stange isn't it ?

Thanks for your help

Thierry

Change the coil pack on that cylinder at $40 for the part on fcp euro dot com and see if they fixes it ... the turbo heat destroys the coils

It makes a lot of sense, coil 2 being just above the turbo.

Thank you so much.

Will change the coil and see if it address my issue (which only happen when the auxiliary heater was just running before trying to start the engine.

Will keep you updated

Have a great day.

Thierry

Hello,
Coil and plug has been changed
Great improvement with still not "stable rpm idle" and light vibration.
It seems that ignition angle (-1) for this cylinder is not in matching the one of the 7 others cylinder (all 0)
Do you believe that there is a "learning period" required to adapt to the new coil ?
Or is it the new coil which doesn't match the 7 others characteristics

Thank you so much

when did you last change spark plugs, coolant, oil? newer sparks r a bit colder, some people go one step colder or gapped tighter.

Spark plugs and liquid changed 4 months/10k ago.

Context :

• After changing one coil and spark plug the relative ignition angle of the cylinder was no more matching the one of the 7 aligned one

2 days later (meaning ' start engine, one night), the cyl ignition angle match the 7 other (sync)

.
I guess that there is a high probability that ECU auto correct the issue.
Is it based on the running time, miles or amount of start/hours, no idea but in all the case it's pretty cool.
Thanks

Very cool!

why not replace rest of coils and plugs - car will be smooth at idle

Context :

• E63s , M157, 2014+, 120K Km
• Issue : Misfire when cold and in un predictable way (not strictly related environment, RPM and ...)
• Symptom : Vibrations. Could lead to Yellow engine dashboard (which could be intermittent)

First try (several defective coil triggering dashboarb):

• Thanks to Peterubers, focalising on the cylinder 2 and 6 (with a probability on cyl 1 and 5 too) which are the most exposed to Turbo overheat
• Full replacement of the coil corresponding of the reported defective cylinder by XENTRY Chassis type / Engine Electronic / Error. It should be noted that Error could be logged without triggering Yellow engine
  -> seems to mean that a threshold is defined (30 or 40 misfire) by cycle triggering. So it could misfire without being reported on the dashboard.
• Result positive (see previous msg) with the discovery that ECU is adapting automatically Ignition Angle. Adaption seems to be calculated during several running time, update being stored when engine is off, car parked for significative time (2 hours or more)
• Stay the feeling the engine is not running smoothly

Determining the issue

• No more error in XENTRY prevent to determine the cause and potential cylinder
• Starting car every morning (cold weather, engine around 40F) with XENTRY test mode running / Engine output / Faulty screen (stacked bar to have history).
• Bingo : Misfire happen interment (no series) but in majority on the cyl 1 2 3 5 6 7.
• Too bad bo more coil set available at affordable price type A2769060501 on the market
• On the basis of :

• Purchase of 8xA2761590242

CAUTION this model is "the new one" which is compatible with A2769060501 and A2769063700. the A2761590042 is compatible with earlier coil BUT not with the new (connection between coil and connector are totally different)

• Extracting the coil thanks above video
• Analysing "potentially defective one"

• Spark side : it's polluted with grease normally present in the tube to ease the remove and prevent humidity-> could explain bad contact (still very high voltage)
• Coil side : the spring is 1 to 2 mm lower than a new one (I guess that pressure + high temperature is making it loose it elasticity)

Applied Fix :

• Installation of the 6 new connectors keeping same coil (sorry guys my old shaking hand where not able to reach/handle the cyl 4 and 8 (which thankfully were not misfiring during test)

-> surprise, the original installed coil are the old model A2769063700

• Start of the engine, not such a great feeling, plug of xentry -> still misfire

Running one full day / parked one night

• HURRA, smooth, no more xentry misfire (including at the very early start of the motor), incredible feeling -> What an amazing engine/car
• Guessing that ECU updated the dynamic parameter to match the new "connector" (drastically improving electrical contact)
• Cost : 8x$20

Lesson learned/Recommendation

• It's worth the value when you are changing the spark plug to change the connector too

Hope it helps

Thierry

I'm not sure what I just read but great write up! So change pencil coils and plugs = no misfire? Seems to confirm what many others have said here. Weak leak in the ignition system.

Thanks. Yes

Sorry not always easy to be synthetic

Context :

• Intermittent misfire (with no continuous Error Engine light on)
• W212 M157 2014+ 120K (coil A2769060501 or A2769063700)

Fix / improvement

• Replace pencil coils (they are sold separately). Ref (for above coil) : 8xA2761590242
• As best practice, replace pencils when replacing spark plugs (it's worth the value)
• Don't put too much grease (to avoid to spread on spark connector)
• Run engine for one or two days before checking if it improved or not.

Thanks

Thierry

Excellent write up - adding to sticky