carver

Hi all,

I purchased a new 2011 E550 2 weeks ago. I've noticed what seems to be a problem but I thought I'd check in to see if it is normal.

When I come to a stop (for a stop sign, or waiting for traffic to clear for a turn), the car hesitates for a second or so before I can get it to go again. It is as if it needs to stay stopped for at least a second or two if it is going to stop.

In this condition, when I push in the gas pedal, the RPMs don't move and there is simply no reaction for about a second, then the car will start to go.

I've put the gear limiter to first gear (and sport mode) to see if it was a delay in down-shifting, but that didn't do it. I tried disabling the ESP to see if it was an ESP function, but that didn't change the behavior.

If I come to a stop and sit for a bit (waiting at a red light, etc), there is no hesitation to go. If it has been stopped for a few seconds or more, the car responds immediately when I push the gas pedal. It is only an issue (and is 100% repeatable) when I come to a stop and then immediately want to go again.

I plan to call the dealership Monday, but thought I would check in here too.

Please tell me this isn't normal behavior for the car.

Thanks.

ttoE550

Sadly, this is normal for the car. Want a really long delay? Reverse, stop, and then put it in drive. Pull out a newspaper because you're going to be waiting a while!

Some people have put an aftermarket "throttle booster" on the car and report happy results. I haven't, but I have found that making quick, successive 3/4 (not full) jabs at the throttle sometimes gets the car moving just after a quick stop. After a long stop, rolling into the throttle (as opposed to quickly flooring it) seems to get it moving more quickly. I don't even mess with the sport mode any more as I find that jabbing the throttle a couple of times is faster than looking down to find the button. But the transmission learns your driving behavior, so maybe my transmission knows I want to go when I give it quick jabs. Even with the jabs, there is still a delay -- just not as long without them.

But nothing I do will get it moving quickly after a reverse-stop.

IMO, this is a safety concern. The car should move when I tell it to do so. There are times when it is perfectly safe to pull out in moving traffic if the car would just go, but is not safe a second or two later. And the delay simply prompts the driver (me) to press harder on the accelerator, so when it finally catches the engine responds with too much torque and acceleration. I don't get it.

ttoE550

I forgot to mention that the throttle also responds quickly if you come to a "hard" stop -- using I guess about 60-75% of the braking power to come to a full stop and then getting back on the gas quickly. I think this also switches it to sport mode, as the car starts in first even without the sport mode button being depressed. But this is an uncomfortable stop for passengers and tends to toss the dog into the floorboard!

carver

Thanks. I must say I'm quite disappointed to hear that this is normal.

I had also noticed the very long delay going from reverse to drive, though that doesn't concern me as much as the basic stop and go delay.

I'll try the quick jab approach you noted to see what I get.

ttoE550

Just wait until you are sitting in the middle of the road while making a seemingly safe 3-point U-turn with oncoming traffic!

K-A

Yup, been there. This car is like an old man with alzheimer's when you do a 3 Point turn. Prepare for a nice looooong delay from R to D when navigating a dire 3 point turn.

carver

I tried the quick double-hit to the gas pedal and it did seem to respond more quickly. (I was already in sport mode so I think there is more to it than that approach making the car go to 1st gear.) The challenge with that, for me, was having it be anything close to smooth.

Any ideas on the background behind the delays? Is it built-in intentionally for some purpose, or is it the side-effect of how something is designed?

SolidGranite

This is not normal. Take it in and I'm sure a fix is available.

Live Oak

Are you sure you don't have it in "HOLD" condition? That will do that.

Otherwise, I sense no hesitation in mine.

carver

Nope. I checked just in case. When I come to a stop it isn't going into hold. I did try a few times putting it in hold to see how quickly it responds. Given that it takes me an extra second or two to put it in hold, it moves immediately when I give it the gas. It is the same good response as if I stop and then wait a couple seconds before trying to go again.

Thanks for the suggestion.

It is interesting to see a mixture of responses on this being normal vs not normal. I plan to call the dealer and have them check it out or comment.

Live Oak

>>>>>>>> moves immediately when I give it the gas <<<<<

Uh, you should easily feel about 1/2 second hesitation coming out of HOLD mode.

Something screwed up there?

??????????

ImInPA

My Bluetec does not experience delays/lag like those being described here. I also just had an E350 4Matic loaner, and it did not experience this either. Sounds like somethign could be wrong here.

chrisvr6

Mine same. I bet it has to think and see if its in sport or comfort then goes into appropriate gear. It really sucks.

ttoE550

There was a very very long discussion of this in this Sprint Booster thread. Some parts of the discussion are useful -- some of it not so much.

https://mbworld.org/forums/e-class-w...t-booster.html

If I remember correctly, the manufacturer of the Sprint Booster said that the throttle can send a more conservative message than you intend with your foot, and this is the cause of the delay.

As the thread points out, the delay is real and simply a feature of our cars. Perhaps those not affected by the delay are just more patient and laid back. The OP describes it exactly right with the quick stop.

carver

I'm taking it in for the dealer to check on Tuesday. When I called they told me it isn't normal, but we'll see what they tell me after they have the car.

I checked out the Sprint Booster thread. Thanks for that. I can see a bit of a lag being normal, but putting the accelerator down most of the way and getting absolutely no response for a second just doesn't seem right.

I'll report back with the findings when there is anything to share.

ttoE550

Yes, please keep me updated. If it is a problem that can be fixed, I'll want to do it. Thanks.

carver

I finally have my car back from the dealer after a week... with no good news.

I do believe this behavior is normal for the E350 and E550. My loaner E350 had the same behavior. I drove another at the dealer and it did the same thing.

I drove with the Quality Control person from the service department. He could tell exactly what hesitation I was referring to, and he told me that's how the 350/550 is designed - whereas the AMGs are more responsive. He thought the reasoning was for a smooth ride without any harsh stop/start jerkiness.

Here's my glimmer of hope: The loaner vehicle I had for a week did the same thing until the last day. The last day I had it, there was no more hesitation and I couldn't even force it to do so despite many attempts. The QC person thought this could perhaps be due to the adaptive throttle/transmission learning what I want after a week of driving. (I have no idea if this is the least bit accurate, but I do know it wasn't hesitating at all that last day.)

The other thing the QC person mentioned is that he knew of someone that had good results with an aftermarket chip (Sprintbooster).

Thanks all for your input on this. I'll give the car a bit to see if it adapts, then I'll consider the Sprintbooster.

ttoE550

Thanks for the update. I am sad that it is normal, but glad there is nothing wrong with the car. I doubt the adaptive transmission unless you were driving the loaner far more aggressively. Please update us if you go the Sprintbooster route, although I don't see myself doing it.

BenzE350

Totally agree. Another design flaw on this car.

Does anyone know if other MB models have the same issue?

6G Schnell

I am new to MB, but based on my limited experience with 2010 C300,2011 e 550 and the latest 2012 C250 there is no delay. As reference point I can use my previous car "the ultimate driving ...." E60 M5 which had a long delay that drove me crazy and made me switch to MB. Just my 2c...

K-A

No delay problems with my 2011's pedal response. These cars are engineered to take off smoothly and without jerkiness, so that may be why some think something is wrong. I think it's just right on my car.

RobbieRob

Welcome to "drive by wire throttle". Drives me nuts. Such a long delay after you hit the peddle and it sends a signal by a wire(instead of cable) to the injection to give it gas...

RobbieRob

The sprint booster sends a more powerful signal(by wire) so things get happening faster. I haven't tried yet, maybe someone on here can chime in on the results after installing.

CEB

And this specifically is the "downside" of the Sprint Booster - it really does nothing but "step on the gas" harder for you.

You can do that yourself.

RobbieRob

No, it sends a stronger current through the wire so it responds faster from what I understand.