O Dogg

I get these on cooler mornings. I'll accelerate, but for a second, it feels like no gas is going where it needs to. It usually does this between 1-2k RPM & is more exagerrated when outside temp is in the 30's. I called my local MB dealership and was told by service tech that this is normal. A safety precaution from MB to prevent harsh driving with a cold engine. To me, this sounds like the opposite of a "safety feature." Random bouts of non-acceleration spell big trouble when trying to make a pass in the left lane.

Once the engine warms up, everything seems to be normal.

Anyone else have this problem?

sosh

Nope, never had this with either my 98 ML320 or my current ML500.

ViKTORiOUS

I have hiccups everyday on my 2002 ML320, so annoying, its not even a smooth acceleration, cause if if i punch it a little, the RPMS go up but the car just revs and then jerks into gear... whats up with that???

drummerboy

I had a similar problem.....The MAF sensor was bad. But it did turn on the CEL.
To see if that was the problem......I just unplugged it, it ran better.

I can relate to your last sentence! Almost got into 3 accidents because of the lack of acceleration problem.

O Dogg

Hmmm...MAF sensor was replaced about a month and a half ago...CEL is off. Something's not right...

pointman

o dogg, sounds normal as long as it goes away after lightly warm.

whatup?

This is normal. I read somewhere that this is due to emissions control. When the car is cold, the catalytic converters do not work efficiently. I think the lag has something to do with helping to warm the catalytic converter.

While I'm not 100% on the exact explanation of what the lag does, but I know it has to do with emissions control.

O Dogg

ahop, I remember posting this before and you responded with the same answer. Thanks for the help. Although, how can it be that a function such as this is "normal?" As I indicated earlier, seems a little dangerous (not to mention aggravating and inconvenient) to me.

pointman

its supposed to be a safety issue to protect the motor and tranny til warm... at least thats what the dealer tries to say. its probably just another crappy ml flaw that they are trying to cover up.

O Dogg

That's what I was thinking myself.

pointman

either way alot of people have it... maybe they dont realize it, but they have it. dont stress it.

Don C

My 2002 ML320 is hesitating also, but not just when it is cold...all the time. It is most obvious when shifting into drive after backing up a short distance (as in pulling out of a parking space). Once in drive pressing on the accelerator reaps no reward of motion for a full 2 or 3 seconds.

It does this at stop lights etc. as well. I took it to the dealer who so far has said that the onboard computer shows no error or problem messages so he concludes that there is none. He said a road test showed no problems.

I'm going back and take one of them with me in the car but would appreciate anyone's thoughts on this.

I am already begining to smell a run-around coming. This is not minor problem. It is so bad that my wife, who is not a timid driver herself, refuses to use the car.

Diabolic

Maybe its the fuel filter.
On the start a fresh injection of fuel can be blocked by fuel debris, when you drive a little bit it becomes smoother.

It could also be the electrical plugs

Or its just the Air sensor.

Check all of these 3.

rizwan

I have the same issue has Viktorious.

Say on my 2000 ML430 I press the accelerator a little deeper to get to get a sudden burst of speed. The revs go up, and after a whole 1.5-2 seconds, it kicks into gear and then I get the power I should have had earlier. It makes lane passing more complicated! I think it should kick into the lower gear sooner.

I understand that this is probably a "safety" feature, or to make the ride seem more "smooth," but does anyone know what I can do about it? Maybe an aftermarket mod?

Thanks,
riz