Camshaft and solenoid sensor replacement
Wanted to see whatevers thoughts about a leaky camshaft sensor and solenoid. Got a 15'-16' E550 (4matic) 136Km on it with the notorious camshaft and solenoid sensor leak. So i unplugged all 8 sensors to clean the wires before it gets worse and noted that only the camshaft sensors (3 of them to be exact) have leaked into the wires while the camshaft solenoid are leaking outside and nothing was on the wires when unplugged and cleaned. Now my question, what would you recommend? Should I only change the rubber for all 8 sensors or throw money and change the whole sensor itself even though there is no faulty sensor just oil seepage. Also almost stopped driving the car just scarred from further damage until I get this issue fixed.




Here's to hoping your Bank 2 (left) solenoids don't require oil filter housing removal to swap like mine did...that job mega sucks. Mine is still ongoing...
Last edited by Jaybird123; Apr 28, 2023 at 03:40 PM. Reason: confused solenoids and sensors re pigtails




Wanted to see whatevers thoughts about a leaky camshaft sensor and solenoid. Got a 15'-16' E550 (4matic) 136Km on it with the notorious camshaft and solenoid sensor leak. So i unplugged all 8 sensors to clean the wires before it gets worse and noted that only the camshaft sensors (3 of them to be exact) have leaked into the wires while the camshaft solenoid are leaking outside and nothing was on the wires when unplugged and cleaned. Now my question, what would you recommend? Should I only change the rubber for all 8 sensors or throw money and change the whole sensor itself even though there is no faulty sensor just oil seepage. Also almost stopped driving the car just scarred from further damage until I get this issue fixed.
As others have already said:
1 - either replace them (best ALL of them) immediately,
2 - or buy the 8 pigtails3 - or at least use an electronic cleaner while you enjoy driving it this weekend (at your own risk).
and when done, for your own benefit try keeping the engine bay as spotless as you can. If something starts leaking, it will be immediately obvious and it will save you $$$ in the long run.
Trending Topics
engine oil and filter change
transmission fluid change
engine air filter change
spark plug change : I also suggest ignition coil replacement above 100k miles / 160k km, it makes a difference
cabin filter change
brake fluid change
brake pads and rotors (if needed)
clean the engine bay!
The above projects will get the car into a known condition. You can decide from there if more work is needed.
The Best of Mercedes & AMG




Tips I can share off the top of my head...
1.) use an 8mm ratcheting wrench in place of the E-torx socket in the tighter spots as needed
2.) If you are loosening the oil filter housing, you may require a new oil filter housing gasket. Mine was rather brittle, though I have ~120k miles on my motor. The real problem isn't the gasket though...its the 2 lower bolts needing loosened or removed on bottom right of housing. They are obstructed by the turbo coolant lines...and as many accurately have stated here, those lines have plastic ends that WILL break when you touch them.
3.) Replacing the turbo coolant lines involves a very difficult to access couple of bolts on side of turbo...I've not yet completed this task
The oil cooler lines come off the top of the oil filter housing easily and should not present much if any oil spill mess. That said, I drained my engine oil prior to starting the job, as I will change filter and give fresh oil upon completion.
Hope this helps, apologies for delayed response. I have been removing my water pump, prepping surfaces for new installs, and dreading the turbo line installs. Good times
Finally...if your solenoids on Bank 2 are NOT faulty, AND you don't need to replace cam chain tensioner...I would consider just adding the pigtails and stopping there? If not broke, why fix...right? It's a pretty deep rabbit hole beyond there unfortunately
Tips I can share off the top of my head...
1.) use an 8mm ratcheting wrench in place of the E-torx socket in the tighter spots as needed
. . . .
Finally...if your solenoids on Bank 2 are NOT faulty, AND you don't need to replace cam chain tensioner...I would consider just adding the pigtails and stopping there? If not broke, why fix...right? It's a pretty deep rabbit hole beyond there unfortunately
engine oil and filter change
transmission fluid change ...
What about the Differential ?
I contacted an indi shop for an estimate and they included the cost for a coolant flush because they said the coolant cooler needed to be removed for the job.
Is that true?
By the way, I contacted a dealer for an estimate and they wanted $1,900 + tax to replace all 4 cam position sensors and all 4 cam solenoid magnets.




If the radiator, the simplest answer would be 'no'...that doesn't need removed for the job mentioned. If oil cooler...it doesn't need removed, but is often leaky and is just below the cam plate and solenoids.
The real question is...why do you need the sensors and solenoids replaced? Sensors are a 5 minute job my kiddo could complete one-handed, so I wouldn't pay anyone to do that. How much less is the dealer quote if that is removed?
3 of 4 solenoids are fairly easily replaced...but the 4th one (on left bank closest to car center) can be a REAL nightmare. That in part led to my water pump, turbo coolant line, OIL COOLER gasket, thermostat/housing, etc replacement...




Let us say, you spent a whole day doing, $900 in parts max, and you can take your significant other for $1000 dinner later
Last edited by JCM_MB; Jun 7, 2023 at 06:53 PM.
If the radiator, the simplest answer would be 'no'...that doesn't need removed for the job mentioned. If oil cooler...it doesn't need removed, but is often leaky and is just below the cam plate and solenoids.
The real question is...why do you need the sensors and solenoids replaced? Sensors are a 5 minute job my kiddo could complete one-handed, so I wouldn't pay anyone to do that. How much less is the dealer quote if that is removed?

3 of 4 solenoids are fairly easily replaced...but the 4th one (on left bank closest to car center) can be a REAL nightmare. That in part led to my water pump, turbo coolant line, OIL COOLER gasket, thermostat/housing, etc replacement...
I need to replace all the sensors and solenoids because I just checked the connectors and they are all leaking oil. The cam position sensors have already leaked oil into the wire harness, but the solenoids haven't. (I can see some oil leakage in the bottom of each solenoid connector).
I haven't had any issues or warning lights in my car yet, but I know this problem can be catastrophic if not fixed.
I've been watching a lot of Youtube videos on how to do this and it seems pretty straight forward. The hardest part seems to be the solenoids if they are blocked by another part. I know I won't be able to move the steel pipe on the passenger side at the bottom because I can't even see where the screw is to loosen it and I'm worried about breaking other things.
I think I'm going to replace the cam position sensors myself since they are pretty easy to get to and I may leave the solenoids in and just buy the sacrificial wire harness for each one. The harness is only $7 each at my dealer. Maybe I'll have the indi shop do the solenoids later on.
Last edited by jumpman726; Jun 7, 2023 at 11:17 PM.
When you replaced your sensors and solenoids did you reuse all of the bolts? Or did you buy new ones? I was planning on just reusing the cam position bolts. I also bought some WD-40 Contact Cleaner to clean the oil from the contacts.




When you replaced your sensors and solenoids did you reuse all of the bolts? Or did you buy new ones? I was planning on just reusing the cam position bolts. I also bought some WD-40 Contact Cleaner to clean the oil from the contacts.
Here is something I ask myself sometimes: "How much difference comparing it (the cost of something) to a tip or a few beers at happy hours?" It is a one-time charge anyways.
Last edited by JCM_MB; Jun 8, 2023 at 08:17 AM.
Has anyone here with a 2012 E 550 installed the sacrificial harnesses on their car?




here is what you want
https://www.ebay.com/itm/37459464874...hoCDHwQAvD_BwE




