mdzukunft

I started with a P0346 code: Camshaft position sensor A circuit range / performance bank 2. There was a fair amount of dried oil and dirt over the camshaft cover so figured the sensors were leaking. I removed them last night and saw oil on the connectors. The solenoid connectors were dry.

I was attempting to remove the intake cover to look at the driver's side today. As I took off the electrical connectors, I sprayed each (both male and female ends) with Liqui Moly Electronic Spray. I wasn't able to actually remove the intake cover, as it turns out but when I got everything buttoned up, the CEL light up with enough codes to light a Christmas tree:

P0010A Camshaft Position Actuator Control Circuit / Open Bank 1

P0013 B Camshaft Position Actuator Control Circuit / Open Bank 1

P0020A Camshaft Position Actuator Control Circuit / Open Bank 2

P0023B Camshaft Position Actuator Control Circuit / Open Bank 2

P0098Intake Air Temperature Sensor 1 Circuit High Bank 1

P0113 Intake Air Temperature Sensor 2 Circuit High Bank 1

P0343Camshaft Position Sensor A Circuit High Bank 1 or Single Sensor

P0346Camshaft Position Sensor A Circuit Range / Performance Bank 2

P0368Camshaft Position Sensor B Circuit High Bank 1

This has to be from cleaning the connectors right? I only removed the passenger side camshaft sensors and re-installed them, cleaned the throttle body assembly. That's it apart from cleaning the electrical connectors.

Any tips or thoughts?

Chevota

So oil all over outside, but none in/on the actual electrical pins/contacts inside, correct? Cleaning won't hurt the contacts, but anything conductive can. Oil isn't very conductive so we can have oil in there, but oil can be dirty which makes it more conductive.
To be clear, you has one code, messed with it, now you have all the codes you listed, right? Hmmm....
That intake does come off, there should be posts about it here somewhere. I think it's just a few bolts and you pry it off?

Have you seen the posts about oil in the cam wire harness? It seems it's fine until it finds its way to the ECU, and especially if it gets inside the ECU. Even if you don't have any oil in there it's something to keep an eye on, but you need to check all the connectors, all 8. One could cause all the problems. So I'd pull the plugs on the ECU to check. I believe the proper procedure is to disconnect the batt, then pull the plugs. Each plug should have a slider lock you have to pull sideways, should be obvious when you see it.
Maybe a long shot, but I made a post about Rats chewing wires and causing all kinds of havoc. So I spoze I'd check for that, and general health of those wires period, but I think you need that intake off to see.

CaliBenzDriver

This is a very productive fault collection.... likely from pulling parts out while the computers were watching the live status.

Have a look at the faults status: current/stored?

Reset faults and scan again afterwards to refresh

mdzukunft

To be clear, I had one code. Car was driving fine. All those codes popped immediately after cleaning this morning. So I don't think this acute issue is due to long-standing oil creep in the harness.

1. Error 1 --> I did not disconnect the battery before removing connectors and the two camshaft sensors in the passenger bank. Oops. Tried resetting the ECU. 5 of the errors came back
2. Error 2 --> The male electrical connectors (engine side) were still saturated with Liqui Moly. My thinking is maybe this is throwing off voltages? Especially since the only similarity between all these errors is that I tried aggressively cleaning the connectors at the same time. So this time, I disconnected the battery and I got my Dyson and zapped each connector (male and female) for a few minutes until I didn't see any more liquid escaping. Going to let them all air-dry this afternoon and evening, the apply some dielectric grease and start again

Any other thoughts?

CaliBenzDriver

sounds like a good solid plan.
​​​​​​Besides, save dielectric grease for other applications.

Cleaning harness oil from :

1. 4x Cam sensors
2. 2x Lambda sensors
3. 2x O2 sensors
4. 2x ECU connectors
5. 1x Oil pump solenoid
6. 🤞

Chevota

You don't need to discon the batt to pull the individual sensors, just the ECU. I don't think it hurts the ECU, but better safe than sorry I spoze.

When I clean my cam connectors, which was twice, I douched them with carb cleaner, blow on them a bit to see if the oil is gone, and back together. So the female side is still full of carb cleaner. No errors. That doesn't really say much, but fyi.

I assume you put the plugs back in the correct sockets? My wires were a length that you can't mix them up, but I rekon not all are that way. Are the sensors and positioners interchangeable? I thought I remember they looked the same, but I recall someone saying no? Anyway, just be sure of the obvious because who knows what that would do. I thought of that because your codes had high readings, like something is pumping in voltage where it shouldn't.

Cali; you forgot to say disconnect the oil pump solenoid

CaliBenzDriver

LOL, I said clean the pump solenoid connection.

Canceling low pressure is a different track. A lot of ppl love their cars stock condition, the way they are, right?

We know why the leaky plastics are toasted but you know better than me how cylinders may cause a pronounced appetite for engine oils.


If we help preserve his engine computer, it'll be a good day.

Chevota

I'll have to note that you didn't suggest to unplug this time.
Some people like bone stock and zero mods, I call those people aliens, likely from Planet X, which is a thing btw.

So far mine hasn't sucked down any oil, but I do have an annoying leak. You'd know if the sensor/positioner plugs are the same or not and can be swapped by mistake, right?

mdzukunft

Well, I buttoned her back up. Down to 5 codes. Car runs smoothly. No hesitation or oddities in operation. Not sure what to make of it.

And there was a tiny bit of oil glistening on my ECU connector (the big one in the front) but no significant pooling by the male pins. So repairs need to be done stat before it gets any worse.

Update: Woke up, turned the ignition and CEL gone. Drove the car ~ 50 mph on highway at normal speeds (after 10 miles of being really ginger with my normally aggressive, Le Mans style of driving). Still operating smoothly. Guess we'll keep monitoring the situation. At best, I'm on borrowed time and I'm sourcing the parts for the sensors, solenoids, pigtails and PCV (there was blow-by in the throttle body assembly).

Chevota

If the codes are gone, then imo, that's all that matters.
Not good on the oil in the connector, but very good you caught it before it screwed things up
I posted a redneck fix for that, if you're interested. Not sure where but it was a thread here somewhere on the oil in the cam wiring. Pretty sure 2023. It's like $5-10K to have fixed, and some actually pay it. Up to you...
Two of my sensors were leaking but I didn't replace them because the redneck fix works so well.

Did another redneck fix (seems to be a pattern for me) for the oil in the throttle body. Also very cheap and very effective, zero oil got past from then on.
Same deal, posted here but not sure where, but that one was ~4-5 years ago when I had the same car as you.

Chevota

That was easy to find:

https://mbworld.org/forums/gl-class-...ml#post8771425

https://mbworld.org/forums/e-class-c...ml#post8135839

mdzukunft

Okay, sourcing the parts for this repair (bought the sensors, solenoids, sacrificial harnesses from ZZPerformance), replacing the PCV system and the start-up rattle TSB (chain tensioners, oil check valves).

Couple of questions...

1. I've read a lot about the breakage of the 6x16mm blue-tipped aluminum cover bolts (578681) with their minimal torque specs. I've also been reading a lot of manufacturers (BMW, VW/Audi/Porsche) are replacing these with stainless bolts during routine service. However, I am unable to find anything from MB re: this. Do you have any ideas?

2. And as far as the solenoid bolts, what sealant would you recommend if one were to reuse the bolts?

3. Regarding the oil check valves, does the M276 come stock with these or were these an add-on? I only want to take the timing valve covers off once so I'm trying to figure out whether I need to buy/borrow a slide hammer to remove stock check valves, if present. I already found the press tool on Amazon for $50.

4. Does anyone have the WIPs for these repairs they'd be willing to share?

Chevota

the tensioner check ball?

WRC-LVR

the 2012 up came fitted with check valves on the oil galleries and camshaft oil galleries, however the first iteration failed miserably causing the knock on start up.. MB in 2014 issued new updated parts and aTSB to be done when the owner complained about it.

If yours is knocking, be sure to use a stethoscope and listen to see if the main and rod bearing have detriorated due to the issue. .While you are in there, use a bore scope as the lack of oil pressure every where is an engine killer.
Please do check out the oil pump solenoid thread here on MBWorld as these and many other MB engines have solenoids that reduce the oil pressure u der certain circumstances. Many people are diabling the solenoid thus allowing full pressure at all loads amd rpms....
YMMV

mdzukunft

Update: So my parts came last night. And the P0346 (camshaft position sensor "A" bank 2) came back (only code this time).

I quickly replaced all four cam sensors this morning (have to get to work). Unable to clear the code with my OBD-II or ECU reset. Engine running fine. Thoughts?

Chevota

That was your original code right? Maybe the wire or plug itself?
Maybe your cans timing plate is too far off? I think the code for that is different, but the ECU isn't very smart, so I'd imagine it's possible.
I'd check cam positions to see what it's reading, so you can see if it working or not, and if so, what is it reading.

mdzukunft

So the codes are all gone (for now). New camshaft position sensors, solenoids and sacrificial harnesses.

When I was replacing the sensors, I happened to already be at 53 degrees that the camshafts all appeared dead center through the ports.

Unfortunately, I popped one of the solenoid bolts on the passenger side exhaust (lowest bolt). It's slowly leaking oil. Once I have a few days off from work (difficult as I'm an ER MD), I plan to remove the cover and try to remove the broken bolt whilst replacing the tensioner and see whether I need the check valve install. Once that is done, I'll do the left-hand side, then tackle the valve covers and the PCV another day.

For the life of me, by the way, I cannot see the camshaft position sensor. Is this even worth doing if there is no issue? I've been reading it is not just a plug and play as the ECU has to be reprogrammed. Advice?

Chevota

You lost me on that last part:
For the life of me, by the way, I cannot see the camshaft position sensor. Is this even worth doing if there is no issue? I've been reading it is not just a plug and play as the ECU has to be reprogrammed. Advice?