Ghostty

Good day everyone,

It has been a while since our cars were made and i hope someone finally figured it out. I am getting more and more annoyed about the transmission adaptive memory. It takes easy 30 mins freeway driving for the car to go into soft acceleration mode, whereas you can floor the pedal but it won't go past 3000rpm and it will accelerate slowly. To get full power back i have to drive around, flooring the pedal almost every time i accelerate. It is really annoying. I did buy the Sprint Booster (pretty awesome thing). Current mode - at 30% boost, i think position 5 out of 9. Gives an aggressive enough throttle response. But the transmission module still kills it.... And i don't want to reset the TCU every week or so in order to keep the full power available at all times.

Did anyone find out a way to turn off the adaptive memory?

Desperate,
Ghostty...

Rudeney

The Sprint Booster should solve that as it would emulate a more aggressive pedal input with less physical travel. I suspect you may have another problem besides just the adaptive transmission going into "granny" mode. You might want to get codes scanned from the TCU using a tool that goes beyond generic OBDII codes and can read MBZ's proprietary systems.

Ghostty

I will double check on the codes, since I haven't scanned the car in a while. But the Sprint Booster solves only the throttle response, not the adaptive mode. Because if I floor it from a complete stop then it will pull as needed, but as soon as I get to cruising speeds it goes in granny mode.

kbob999

Interesting observation...My 3.0 Bluetec has the 722.9 adaptive tranny, but I never notice 'granny mode' or need a quick downshift as the diesel has 400 Ft.-Lb. of torque at 1600-2400 RPM.
Adaptive trans is probably not needed, or used, on the V6 diesel. Last time I reset the TCU I noticed no difference.

Ghostty

Kbob999,

you have the peak torque basically from the idle rpms. If i remember correctly, for the the top torque for V8 is at about 3000 rpm, exactly where it up-shifts to next gear. The transmission goes all the way to 6th gear (or 7th, don't remember total number ). So it's not a limp mode or something. If it would have been a TCU/ECU issue or something like that - most likely it would have thrown a "check engine" code at least once. None observed.

I.E, today i drove the car around, flooring a little more often - it did "program" itself to be more responsive and it did give me full power no matter how i drove. After a 30 min freeway driving - back to soft acceleration. Drove again more aggressively - back to full power. As i said, i could reset the TCU through the reset mode (turn key to 2nd position, floor gas pedal for 15 secs, turn key off, wait for 2 mins). But don't want to do it too often. But looks like i won't have many options

Ghostty

Hary Gahtoe

Ghostty

Hary,

Maybe it's just me, but i decided to keep it at a lower boost. I tried at the time to max it out and it was too jerky... But i'll try again, maybe it was just me who didn't get it right
So i will play around a little and boost the signal to give it a shot.

No negative issues, just increased responsiveness. It does make a difference, even if you just tap the gas. Comparing to how it was without the boost - night and day. I was not able to spin the tires whatsoever without it, now i can do it at any time even with this low setting. The throttle responds at any time i press gass, it's just the adaptive module that kills me

Ghostty

Hary Gahtoe

Ghostty

Yes, I totally agree, it does not add hp. I love the booster, made the car feel more alive! Just trying to figure out my issue))

Rudeney

I had also discounted the Sprint Booster as "snake oil", but then I watched a video showing the throttle actuation as the accelerator pedal is pressed. As delivered from the factory, one could slam the accelerator down fast and hard, yet the throttle just slowly opened, taking a second or longer. With the Sprint Booster in place, the throttle snapped open just as quickly as the accelerator was pressed. While this won't increase HP or torque, it can shift those curves on the timeline so they peak more quickly. That can definitely affect real-world performance numbers like 0-60. I still have not bought one yet, but it's on my list, along with several other frivolous purchases to be made as soon as my discretionary spending fund is healthy enough.

bobterry99

Years ago I watched an episode of Top Gear which featured an R230 with an engine modified to produce vastly more torque and horsepower than stock. The show setup a drag race with another vehicle. Upon launch the R230 went nowhere -- it just spun its rear wheels and generated prodigious smoke. A bicycle could have beat this R230 down the track.

I presume the throttle is opened over the course of a second or two to prevent the rear wheels from spinning, and in this case it would launch the car quicker than if the wide-open throttle occurred immediately. I also presume that it may be opened conservatively to avoid wheel spin in cases where road surfaces and tires yield diminished grip. If so, then with good tires and a smooth, dry road a Sprint Booster would improve performance.

Rudeney

It really is a mystery to me why drive-by-wire throttle are slow to open like. It very well may be to prevent wheel spin, but it also does this at highway speeds when you need to pass and it can be very annoying. It's even the same delay on cars with engines not powerful enough to spin the wheels. And besides that, ESP can be tuned to prevent wheel spin, so why mess with the throttle speed? My guess is that it's either a comfort thing so that the throttle doesn't feel too touchy, or it may even be a fuel savings strategy.

On my SL550 with new tires on a dry street, I cannot make the tires break loose. With the transmission in sport mode and 1st gear selected, I can stand on the accelerator and it will take off quickly, but not enough to spin the wheels. The CLK550 I had with the same engine and transmission (though it had VGS2 vs. the SL's VGS3) would spin wheels easily. The tire size was smaller 17's vs. 19's and narrower, so that might contribute. Plus the CLK was just a bit lighter.

I don't want a Sprint Booster in order to smoke my tires. I would simply like to fix the lag I feel int hose time when I want to quickly accelerate.

Ghostty

Correct, and the booster does a great job with improving throttle response. I don't use it to spin tires and burn rubber either, just before installing the system my FX37 was way quicker. Now at least doesn't feel as sluggish.

Definitely tire size and car weight have impact on that. Maybe you are right - R230 is a grand turismo type of car and the while building the throttle engineers kept that in mind. I would say the system backfired by not providing quick acceleration when needed. Same time all the old cars have similar responsiveness, so not to blame the engineers. But the adaptive module - probably more people dislike it than like it...

Hary Gahtoe

Ghostty

So update on my issue:

Took the car for a trip a little over 1k miles. Only if the weather in LA would be more sunny that weekend The Fomula Drift championship was awesome! Will visit next time as well. On the way to LA had the usual little power or no revving over 3k RPM. At least i was exhausted enough to enjoy the easy ride not to care. When i drove it locally and on my way to San Francisco the car was actually very responsive to the throttle. Driving in bay area - all good, as expected. Drove home to Sacramento - same thing - good response, full power available... What is this vehicle's issue? No clue. Will have it scanned with a scanner probably next week, or whenever will get a chance.

Same time enjoyed the drive - definitely a car to take for long trips - drove about 3 hours straight on 4 different occasions. Loved every moment

The only thing that got me a little tired - my right foot position. I'm 6'5" and when driving i bump into the panel with my knee. Moved back the seat a little to get more room but still can't say that i was that much more comfortable driving it. I guess being tall and having long legs it's a problem even in the mighty SL So some more stops during long trips or a copilot will solve my problem

P.S.

Hary Gahtoe,
i have it maxed out actually. I guess i didn't check the mode for a while and assumed it was on a low setting. Maxed out and kept it that way the entire trip. I've also figured out how to minimize the load on the transmission when down shifting and accelerating to minimize jerking the car