Sluggish acceleration - dealership said everything is fine
09-07-2022, 02:16 PM
#1
Sluggish acceleration - dealership said everything is fine
Hi all,
I just bought a 2020 GLC300 2 months ago and it is still under warranty. Past 2 weeks I noticed the car is struggling to accelerate. RPM needs to go to 2-3000 to go from 0 to 30 and to reach 50 it sometimes shoots up to 5000. It also takes way longer to accelerate on the highway to change lane.
Brought it in for inspection and today got the reply that everything looks fine (performed extended road test, sds quick test, scanned for code). They suspect I might have "engaged manual shift mode on the back of the steering wheel and locking transmission into first gear"
I'm pretty sure I'd know if the car is switched to manual mode. Display is still showing D1, D2... as I accelerate, and even if I touched the paddle shifter, it'd just be a temporary gear shift. What do they mean by "locking transmission into first gear"?
Also, what are my options now? Is there any quick fix I can try myself or should I bring it into an independent shop to have a look? Thank you
I just bought a 2020 GLC300 2 months ago and it is still under warranty. Past 2 weeks I noticed the car is struggling to accelerate. RPM needs to go to 2-3000 to go from 0 to 30 and to reach 50 it sometimes shoots up to 5000. It also takes way longer to accelerate on the highway to change lane.
Brought it in for inspection and today got the reply that everything looks fine (performed extended road test, sds quick test, scanned for code). They suspect I might have "engaged manual shift mode on the back of the steering wheel and locking transmission into first gear"
I'm pretty sure I'd know if the car is switched to manual mode. Display is still showing D1, D2... as I accelerate, and even if I touched the paddle shifter, it'd just be a temporary gear shift. What do they mean by "locking transmission into first gear"?
Also, what are my options now? Is there any quick fix I can try myself or should I bring it into an independent shop to have a look? Thank you
09-07-2022, 05:16 PM
#2
Super Member
You could try resetting the transmission to relearn your drive style. There is a post or two around here as well as on YouTube in how to do it.
09-08-2022, 09:56 AM
#3
09-12-2022, 12:32 PM
#5
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Join Date: Mar 2007
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2020 GLC300 & 2009 SL550 (previously had 1999 CLK / 2006 E500 / 2011 GL450)
I would run down what you have and try about 10 gallons from somewhere you’ve had good experience with (if the last batch wasn’t your usual station). If you bought in your usual place last time, try a different station or brand (stick to the majors if you have those options — BP, Exxon, Shell, etc.
My car seems to like BP and Shell the best, though I only put Exxon in a few times since not as convenient.
