Mr. Toad

My car has the V6 twin-turbo (M276) engine. While facing the engine from the front bumper and moving from left to right, I was able to unplug the second, third and fourth Camshaft Adjuster Magnet connectors and all were dry, but I cannot get to the first one on the left, which is hidden behind a white plastic fluid reservoir. Can anyone explain what's required to access this first Camshaft Adjuster Magnet? Do I have to unbolt and remove that fluid reservoir?

Also, I noticed that the plugs that connect the Camshaft Adjuster Magnets on the front of the engine are different from those that connect the Camshaft Position Sensors. The plugs on the Camshaft Position Sensors don't have the same white plastic part that can be pushed down to unlock the connector. Can anyone explain how to unplug the Camshaft Position Sensors?

Finally, if I understand correctly from FCP Euro, the so-called "sacrificial pigtail" (i.e., MB Part # A2711500156) is not officially applicable to my car, but will fit the Camshaft Adjuster Magnets on my engine. However, as the connectors are different for the Camshaft Position Sensors, does anyone know the part number of the pigtail that will fit them?

TwoC400s

Yes, you'll need to be able to move the IC reservoir around. There are 2 E10 etorx bolts and one t40? 35? Screw that hold it in place. Once those are out you can push it out of the way.

I am also curious about the camshaft position sensor harnesses. The 3.0L position sensors are pn: 2769050900.

Not sure if anyone makes an aftermarket pig tail for them yet.

TwoC400s

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​​​​Maybe @S-Prihadi knows?

vincheung

I'm fairly certain the referenced CPS harness extension kits will also fit the m276. If you have some photos of the actual sensor connection post them up and we could possibly help confirm visually.

chassis

M276 pigtails are available. Well documented on this site.

Mr. Toad

As I noted in my previous post above, per FCP Euro, the so-called "sacrificial pigtail" (i.e., MB Part # A2711500156) is not officially applicable to my car, but will fit the Camshaft Adjuster Magnets on my engine. However, as the connectors are different for the Camshaft Position Sensors, does anyone know the part number of the pigtail that will fit them?

bloxham

On my C350 M276 (2012) I was checking my camshaft position sensors for oil and changing the serpentine belt. Thought I'd look for the timing marks 40 and 53 degrees on the crankshaft pulley. The only marks I could see were the MB part number and that was only just visible, no timing marks visible at all. Anyone had experience of this ? Or is it just me ?

new550

Hello team !!! 2015 s550 with108k miles....M278 engine....

So....I read these threads and checked my cam position sensors and cam solenoid magnets....GRRRRR......3 out of 4 sensors leaking into the wiring harness connectors, but luckily the magnet connectors were all clean....I have cleaned up the mess in the connectors and ordered/installed new cam position sensors and the sacrificial harnesses for both sensors and for the magnets (as a preventative measure).

My question is how to safely check the ECU side of the harness for any leaks needing cleanup....can I just disconnect the harness connector(s) without damaging the ECU or causing any software/settings glitches or do I need to follow a specific w222 procedure?

Thanks in advance for any help you can provide!!

TimC300

I would disconnect the battery before unplugging any connectors.

bloxham

Turn engine off, remove key and leave for 15 mins to ensure everything shuts down properly. Then you can safely remove the ECU plugs. Leave all the doors closed so nothing wakes the car up. This is how I did it. Yes you could remove the battery but I didn't & had no problems afterwards.
There was just the slightest trace of oil on the front ECU plug (the one marked M). I removed the plastic cap off the plug and cleaned it all with contact cleaner spray, then reassembled. Also used a vacuum cleaner with a home made plate to such any residual oil from the plug; not sure how effective this was though. (My car is an M276 engine but just 2 cylinders less than yours). I also removed the ECU & cleaned the contacts with contact cleaner spray.

Reassembled & all is ok, I will recheck in a couple of weeks.