Unresponsive Acceleration- Help!!
Thread Starter
Newbie
Joined: Jul 2012
Posts: 10
Likes: 0
MB S55 AMG
Unresponsive Acceleration- Help!!
Newby here........
I bought a 2007 S550 with 74k Miles a couple of days ago. During the test drive everything went fine. Took it on a long drive no issues at all.
However, something really strange happened this afternoon. I was cruising at around 75MPH going up a long steep grade then all over sudden, the car felt like it lost acceleration power. I mean, it started slowing down while I still had the accelerator pedal pressed. I even tried the pedal kick/down, flooring the car but still it didn't want to kick into overdrive.
While still on steep grade, I attempted to cruise it, set it to $85MPH, it didn't pick any power at all. So I took the next available exit. Once I reached the end of the exit ramp, the car would not move at all. It simply revved. No Mulf indicator light. So I turned it off. Then back on. Put it into 'D' then everything was perfectly fine afterwards.
I have been driving for a solid 2 hours since the problem happened and it seems fine now.
A few questions;
1) I know the W220 is common with faulty Accelerator Pedal. Is it possible that I need a new Accelerator Pedal Module on my S550?
2) Does this correlate to the dreaded Transmission problem on the W221?
If you have any information that might help, I will greatly appreciate it.
Thanks.
I bought a 2007 S550 with 74k Miles a couple of days ago. During the test drive everything went fine. Took it on a long drive no issues at all.
However, something really strange happened this afternoon. I was cruising at around 75MPH going up a long steep grade then all over sudden, the car felt like it lost acceleration power. I mean, it started slowing down while I still had the accelerator pedal pressed. I even tried the pedal kick/down, flooring the car but still it didn't want to kick into overdrive.
While still on steep grade, I attempted to cruise it, set it to $85MPH, it didn't pick any power at all. So I took the next available exit. Once I reached the end of the exit ramp, the car would not move at all. It simply revved. No Mulf indicator light. So I turned it off. Then back on. Put it into 'D' then everything was perfectly fine afterwards.
I have been driving for a solid 2 hours since the problem happened and it seems fine now.
A few questions;
1) I know the W220 is common with faulty Accelerator Pedal. Is it possible that I need a new Accelerator Pedal Module on my S550?
2) Does this correlate to the dreaded Transmission problem on the W221?
If you have any information that might help, I will greatly appreciate it.
Thanks.
MBWorld Fanatic!
Joined: May 2008
Posts: 7,653
Likes: 560
2016 C300
When you were on the grade and applied more throttle did the RPMs increase while the cars speed stayed the same? That sounds like a tranny problem to me. I had one in my 220 do the same thing (although once it started slipping it completely disengaged and I couldn't get anything more out of it.) Yours may just be a tranny service to replace the fluid and filter and see how much metal shaving is in the pan. It needs to get to a decent Indie or a dealer. Your basic transmission shop won't do. The 7 speed reman'd and installed was $6k when mine went. Good luck!
Thread Starter
Newbie
Joined: Jul 2012
Posts: 10
Likes: 0
MB S55 AMG
Thanks for the response. Nope! The RPM's didn't increase or Revv up while power loss occurred on steep grade. The best way to describe it; The car felt like the tranny was locked up in 7th gear instead of overdrive kicking in to compensate for power needed to tackle the steep grade. But of course without the usual vibration feeling like climbing a hill with a higher gear manual transmission car.
When you were on the grade and applied more throttle did the RPMs increase while the cars speed stayed the same? That sounds like a tranny problem to me. I had one in my 220 do the same thing (although once it started slipping it completely disengaged and I couldn't get anything more out of it.) Yours may just be a tranny service to replace the fluid and filter and see how much metal shaving is in the pan. It needs to get to a decent Indie or a dealer. Your basic transmission shop won't do. The 7 speed reman'd and installed was $6k when mine went. Good luck!
MBWorld Fanatic!
Joined: May 2008
Posts: 7,653
Likes: 560
2016 C300
Safe to say it's an internal tranny issue at this point. The question would be how severe. I was unable to find a shop...indie or dealer...who thought it was a good idea to try to rebuild and repair the tranny. Too intricate, and the indie pointed out that a reman'd would cost about as much as the labor required to rebuild the old unit, but come with a warranty. Once a bunch of little metal bits start running around in the innards its pretty much over. New torque convertor for the same reason (included in that $6k figure).
Not to scare you...yours may be something as simple as a sticky valve somewhere...but it needs to go to MB or a good indie for diagnostics and probably a few hours labor to crack the case and poke around.
Any chance there's an aftermarket warranty on her?
Not to scare you...yours may be something as simple as a sticky valve somewhere...but it needs to go to MB or a good indie for diagnostics and probably a few hours labor to crack the case and poke around.
Any chance there's an aftermarket warranty on her?
Junior Member
Joined: Aug 2014
Posts: 57
Likes: 10
From: Zurich
S500 4M L
Hi,
try to switch to M (manual) when you have acceleration issues and then try to up/down a gear using buttons on the back of steering wheel. If you will see on display that gear will not change means common issue with ASB (probably code P276).
I have the same issue.
First - replace oil in transmission. It could help a little - error will occur not often (in my case).
Second - repair your transmission - MB sells electronic module (about 1000$ in my country). There are a lot of service shops which repair this electronic module (replace solenoid) it is much cheaper (in Poland around 250$).
I'm heaving this same issue - for 20k mils it occurred 5-6 times so I ignore this for now.
Keep us updated.
Good luck !
Mariusz
try to switch to M (manual) when you have acceleration issues and then try to up/down a gear using buttons on the back of steering wheel. If you will see on display that gear will not change means common issue with ASB (probably code P276).
I have the same issue.
First - replace oil in transmission. It could help a little - error will occur not often (in my case).
Second - repair your transmission - MB sells electronic module (about 1000$ in my country). There are a lot of service shops which repair this electronic module (replace solenoid) it is much cheaper (in Poland around 250$).
I'm heaving this same issue - for 20k mils it occurred 5-6 times so I ignore this for now.
Keep us updated.
Good luck !
Mariusz
