GinDistiller

Posting this here because it's much more active than the GL/X166 forums, but same engine/same problems (and thankfully my E63s is good for now...)

Most/all threads concerning this are either people paying out of pocket, or a warranty repair because of a direct failure of injector/sensor etc, I'm in 'early' stages.

Here's where I'm at and would love opinions, ideally from people who have had the engine harness repairs done w/ an aftermarket warranty company.
Bought our '13 GL63 w/ 69k miles, came with 2 years left on AGWS Platinum warranty. During PPI, found small amount of oil in several cam sensor connectors and one cam magnet. No other issues reported. I immediately replaced with 8 new sensors, updated part numbers, and cleaned connectors.

Fast forward to now (86k miles), we've been having some general lack of performance, transmission shifting has been erratic at times, and some odd electrical symptoms. Plus a evap leak code despite having a new solenoid, charcoal canister and valve, and fuel cap. I know these could all be separate issues, but I've also seen this reported in cases of oil contamination. Sure enough, pulled ECU and found oil in multiple pins, and despite having less than 20k miles on them, ALL cps connectors are soaked in oil (worse than when I originally replaced them...). All service is up to date, no error codes besides that emissions one but it only trips every month or two.

We LOVE the car, have a third kid coming in October so we need 3 rows and I will jump off a bridge before buying a minivan. I know we could trade it in, but I'd just want another and feel like I'd be better off with mine knowing all of the other maintenance history. Can't afford a newer gen as that is $20k+ more expensive with how current prices are.

So, big question: Has anyone had an aftermarket warranty company cover engine harness replacement before it's caused an injector or coil to stop working etc? I have no doubt a failure will occur at some point with the oil I'm seeing, but since I have less than a year left of coverage I'm hesitant to clean it in case it causes it to last past the year and then I'm on my own.

And, with the ECU possibly involved, do I need to keep this to a dealer or can I use an independent? I much prefer independents, but I also know the dealer has likely seen a lot more of these repairs.

Step 1 is to bite the bullet and take it in for a diagnostic, I'd just love some advice around the oil knowing that is a ticking time bomb at this point... Thanks all!

JEC_E63S

Just finished with all of this on my 63. Warranties are completely different depending on the company as to what they will and won't cover. My aftermarket warranty covered anything that had "failed to do it original intended duty", i.e. it covered the CPS, mags, oil pressure solenoid and the labor involved to fix these. It did NOT cover the replacement of the harness (soaked in oil) because "it still emitted signal from A to B" they suggested to clean it. My tech wouldn't do the repair if he had to clean it. So to replace it was out of pocket. The oil pressure solenoid requires the motor to be pulled out to replace it, at this point, with someone else (warranty) covering that labor, we went ahead and did all of the M157 preventative maintenance as well, i.e. turbo cooling lines, engine cooling lines, front motor seals, front diff seals and several other items. All of that was an out of pocket expense as well.

Good luck, it's a hard decision at best. I've done all of the work, but currently am trying to move on from the car and sell it. Logic states that the Genuine Mercedes parts that failed the first time and were replaced with the same Genuine Mercedes parts, will fail again. And I don't want to face that without a warranty. Unfortunately, I expected a lot more from Mercedes than this. I understand I bought a performance car, but these aren't "performance" issues, this is just crap parts and engineering with an exorbitant price tag to not even truly fix, but simply band-aid.

GinDistiller

Thanks, and that is kind of the answer I suspected. Glad to know they covered labor to R&R the motor, I'd be happy to cover extra preventative things like that too. Was this at a dealer or independent shop?

The thing is, I have an engine hoist and a lift in my garage and could do the job myself, I just (obviously) don't want to. Especially while I still have some warranty coverage.

I forgot about that oil solenoid, so I'm thinking I'll check that soon and if it's not wet, maybe wait until it is so the big labor could be covered. If I didn't have a warranty I'd probably try the multi-day cleaning/drying/cleaning etc and keep an eye on things.

Does anyone have a picture or description on where the oil pressure solenoid is? Google is not helpful with that one, not sure if it's like the old level sensors on the bottom of the pan or if it's somewhere else.

JEC_E63S

yep, I got you. Lol All of my work was done at an independent shop, but AMG certified. Here’s pics of the pressure solenoid, and yes, it’s in the pan under the motor.


Bottom Of motor off showing internal solenoid. (Top right)

Exterior plug that reads the pressure solenoid.

GinDistiller

Thank you sir! That is super helpful!