[300SDLGUY]

A month ago I brought my car, with only 20,000 miles on it, to the dealer to have the soft close failure on the front door (still not working correctly) On my way home I stopped to run an errand, and when I got back in, and restarted the car it went into "limp mode". I immediately drove 30 miles back to the dealer. They diagnosed it as the right coil, and replaced it under warranty, but did state that when one coil fails the other will probably fail relatively soon afterward. Last Wednesday morning I started it and it immediately went into "limp mode". I was running late, so I had to drive it, but after about three restarts during the day, it went out of "limp mode". But there was now a slight miss, and check engine light remained on. I brought the car to the dealer the next day with it misfiring and check engine light on, but not in limp mode. Today they called to say that they could not get it to go into "limp mode", and the check engine light went off while in the shop, but there are stored codes: P2050 misfire, P2051 Cyl#1, 2055 Cyl #2, 2057 Cyl# 7, 205B Cyl#8. They said in an effort to solve the problem, they replaced the ABC pump, saying that sometimes it can cause misfiring (never heard that one) but really they probably changed it because Mercedes paid them to under the ABC campaign. I was told to come pick up the car as there is nothing more they can do. I asked why they couldn't replace the left coil and was told Mercedes would not authorized it or any other parts replacement under warranty, because there are no active codes and the check engine light is no longer on. Has anyone had any experience with this issue and/or dealing with or complaining to Mercedes about warranty replacement? Thanks!

 

[81240D]

mb

What dealership did you used ?

The door soft close failure

could be the fuse or vac line or vac pump
try the fuse

engine misfire

engine control module ?

 

[Oxygen__]

What exactly is "limp mode" and why is it in quotes? LOL

Limp mode is when the transmission allows you to drive home in one or a few gears... your issue is not transmission related, so what do you mean by "limp mode" ? What is the behavior?

 

[autospeed]

Limp mode from what I know is also a safety feature in the ecu for the engine where it'll let you get home or to the stealership, but with very limited power (ie: severe rpm cut-off). I've personally never heard of the abc pump having anything to do with it. See how it drives now, if its fine then they took care of it, if not I'd write a letter of complaint to mercedes, and see you can speak to a manager at the dealer. Its ridiculous when you buy such a pricey (but nice) vehicle that they just tell you there's nothing else they can do. Worst case scenario try and find a really good independent mechanic.

 

[300SDLGUY]

What dealership did you used ?

The door soft close failure

could be the fuse or vac line or vac pump
try the fuse

I use Bud Smail in Greensburg, I had used Rahal, but became unhappy with their abilities.

They changed the door handles (not sure why), they checked the lines etc. They obviously did the fuse trick to make is work sometimes, but they said they couldn't authorized a pump replacement under warranty because they system worked properly enough. They even had the audacity to tell me that maybe the car had been wrecked and not repaired properly. If they'd have looked, they could have seen the car was all original, never been painted on, and vin#s on door etc. Ultimately they adjusted the door latch and made it close easier, but now it just closes without the use of soft close even though closing the doors the same way on the other three results in a soft close. I was done, I just wanted my car back. But, then of course, the misfire issue occurred. *

 

[300SDLGUY]

What exactly is "limp mode" and why is it in quotes? LOL

Limp mode is when the transmission allows you to drive home in one or a few gears... your issue is not transmission related, so what do you mean by "limp mode" ? What is the behavior?

LOL is right....GOOD GRIEF! I used quotation marks because I wanted to ultimately. My use of them, as I used them, are correct, of this, I have no doubt. <grin>

That being said, you are correct about a couple of things, my misfire issue was/is not related to transmission failure, and you are correct again, with your knowledge that when a vehicle goes into "limp mode" it can/does limit the used of certain gears (usually the first gear BTW). But "limp mode" in your, and my s600, causes power to be reduced by shutting down an entire cylinder bank, thus allowing the car to run on only 6 cylinders.

 

[300SDLGUY]

Limp mode from what I know is also a safety feature in the ecu for the engine where it'll let you get home or to the stealership, but with very limited power (ie: severe rpm cut-off). I've personally never heard of the abc pump having anything to do with it. See how it drives now, if its fine then they took care of it, if not I'd write a letter of complaint to mercedes, and see you can speak to a manager at the dealer. Its ridiculous when you buy such a pricey (but nice) vehicle that they just tell you there's nothing else they can do. Worst case scenario try and find a really good independent mechanic.

Thanks for your eloquent explanation for Oxegen. I totally agree that its ridiculous to have to have so many issues with these cars, let alone have authorized/certified Mercedes service departments that can't seem to get the job done.

Here is what I did, I actually found out that there is a Technical Service Bulletin about this very issue:

Order No.: P-B-47.20/31

Supersedes:

Group: 47
SUBJECT:
Model 215.376 Model 220.176 Model 230.476 with Engine M275

Hot Start Performance Complaints with Winter Fuel Which Contains Ethanol

If you receive customer reports in the above model vehicles of hot start performance complaints, mainly in areas where winter fuel contains ethanol, proceed as follows to resolve.

Note :This applies only to vehicles with the check engine light activated and misfire codes on the front cylinders (i.e. cylinder number 1, 2, 7, 8) where the freeze frame data indicates that the misfire was detected immediately (up to 1 minute) after engine restart at operating temperature (Figure 2). All other cases, proceed as outlined in V12 Engine Complaints Diagnostic Tree located on STAR TekInfo (EDAC)."

So, that's what they did, of course I am none too happy that I was the one who had to tell them there was a TSB about it.

With respect to the ABC pump, my service advisor told me that sometimes they the pump can cause the check engine light to illuminate and throw some code(s), I wasn't really sure, but if it fixed the misfire I wasn't going to argue. It appears they replaced it because there is a TSB about its replacement. Not sure how they found the ABC TSB and not the Fuel Pump TSB.

Anyway, got the car back and it runs like it used to, for now anyway.