Streamliner

I am getting a "nervous" idle. It's not enough to show on the video game tach, but it's annoying. I am running 76 premium gas. My W221 never did that. Anyone else have this problem?

DaveVY

No problem with our 2014. Let us know what you find out about this.

jenz

Haven't you posted elsewhere about running regular gas in your S with no issues?

RajwanyS550

premium or super is 91 and onward not 76.
what gas are you actually running. please elaborate.

PeterUbers

76 is the brand, buddy

There, he is buying premium fuel

Hope that helps you.

Streamliner

I ran my 2013 S550 on regular unleaded exclusively and never had a problem. I noticed this rough idle in my 2015 after about two tanks of regular and switched to premium, but no improvement.

Streamliner

In Southern California, Union 76 is a top name brand gasoline. I buy their premium unleaded.

emilner

My car is smooth as butter. I have to look at the tach to see if it shut off or is running, you really can't tell. Perhaps the regular gummed up something. I doubt it would happen so fast but maybe. Still couldn't fathom putting regular in an S class though....

hyperion667

butter for me too......wait, I don't have a 15

Long3494Qut

Smooth on my end as well. Only once did it do what my E classes did and shook the car abit as it was on idle on a cold start. Drove it a mile and it stopped. No biggy.

Germancar1

So wait, regular was used and now the car idling rough? Why in the world would anyone buy a 100K and then skimp on gas is beyond me. I don't get the point of threads like these.

M

steveb9771

Try adding Techron to a couple of tank fulls

PeterUbers

It's a 2015 with a rough idle... Just take it in

Streamliner

I will. It's not a big enough problem to hassle a dealer visit yet.

Pmurray633

To this point, I was at the dealer this morning getting a wash before the gym, guy came in to get his car washed (2015 S550) and complained "when I am at a light, the damn engine turns off and then turns back on, there is definitely something wrong with this vehicle you've sold me"

Guy was maybe 80 years old and obviously didn't know the first thing about his car.

Streamliner

The ECO feature is quite annoying, especially since it cannot be permanently turned off. MB needs to fix this and allow customers the option of turning it off once and for all, as BMW has done.

Red Marko

Any tuner will turn ECO off. Permanently.

On the subject of running low octane fuel in your car. Don't listen to anybody, keep doing what you're doing, I'm doing the same thing.
On a secret note, I'm peeing into my tank on regular basis. As long as it contains high levels of ethanol (as mine does), you will be fine and you will continue to save money.

hyperion667

emilner

Just curious, what's annoying about it? I find it shuts off with barely a peep and startup is seamless. It saves a good amount of gas in stop and go driving...

Streamliner

Well, like so many things about these cars, I guess it's a matter of opinion. I find it very annoying and I do believe, that if we took a poll, most folks on this board would say that they would much prefer being able to turn it off permanently. In addition to finding it annoying, I dislike these "big brother" kinds of things. I like to be in control of my vehicle, not the other way around. That said, if you like it, that's great and I'm happy for you.

Wolfman

Really???

I have not heard of anyone in the US defeating the MB ECO system. In fact I only know of one company worldwide to offer this (don't remember if they are inGermany or Switzerland).
Please share specifics...

Red Marko

Really,
rather basic, first tier to implement. Believe it or not, MB's electronics are not bulletproof.

If you want me to do your search for you, please send $5.00 Subway (or Starbucks) coupon to my location.

Wolfman

I am sure it's not difficult to defeat; I just haven't seen anyone in the US do it.
The phrase that every tuner does it just BS.

Just name a couple...

s550nothappy

I am getting the same rough idle when Eco is off either in Park or at stop with foot on brake. The only way I can describe it is that the car gets a shiver. It can happen when car is cold or warm. Nothing shows on the tach, but you can feel the car shudders.


Techs tell me they don't feel it.

Streamliner

Living with this problem for about 3,000 miles now (too much going on/no time to take back to dealer) I find that when I am in bumper to bumper freeway traffic, just creeping along, it becomes very annoying. When I am just lifting my foot slightly off the brake and letting the car creep forward at idle, the shudder is quite pronounced and I feel it coming through the brake pedal and the steering wheel. The next time I take the car in for service, I will be able to easily demonstrate the problem, so there should not be anymore of this "cannot duplicate" crap. AND, I have been running premium gas exclusively and I did try adding Techron, with no improvement. At anything above idle speed, the car runs great.