c230_kS

i have an c230 sedan auto, when i tried to have the car in 1st and let it shift itself into 2nd. the car has big jerking (or kick back) feeling like the feeling you get when you drive an manual .... is this normal? because it doesn't happen when the car shift 2nd to 3rd by itself (it smooth..) is it just the way transmission is program so the made the car more aggressive on the low gear or something that i should take it to dealer....

MikeSL5

it does usually happen but you shouldnt feel it too much

c230_kS

i see, so 1st to 2nd is rougher compare to higher gears?

MikeSL5

On my C230 sedan its not that rough from 1st to 2nd but I have heard from others that its a little rough. Search the forum. There have been topics about this before.

c230_kS

so do you consider your 1st to 2nd "really smooth" or not that rough...but still tiny rough. and are you talking about this base on a straight line accleration?

E55AMG99

Does it happen every time under full throttle or only after you downshift into first gear and then floor it?

moomeh

first 15k i had this jerk when still warming up. now, with or without warming up i have a nice silky shifting from 1 to 2.

c230_kS

downshift into 1st and then floor it. and it jerks when the car is cold still... i guess its' normal? ..

jpb5151

You downshift to 1st and floor it when the engine's cold? ??

c230_kS

haha... sorry my bad... i mean downshift to 1st and floor it so it will shift itself into 2nd
also, when the engine is cold, the 1st to 2nd gear chokes

E55AMG99

Some cars have this problem that if allowed to downshift into first and full throttle is applied, they hit the rev limiter before shifting into second. I first encountered this problem in '99 with my E55. At a 25 MPH cruise, floor the throttle. Car downshifts to 1st, tires chirp, ESP kicks in. Power restored, engine races to redline and hits rev limter. ECU cuts power, tires chirp (comression braking). Trans shifts to second, ECU restores FULL power, tires chirp, ESP kicks in. Tires regain grip, power restored. FUGLY!

According to MBUSA, they never heard of this problem before and used my car to test different "fixes" After replacing the shifter, trans valvebody (with MY 2000 unit), trans ECU, engine ECU and various sensors, the problem has been reduced but not gone. I also had my ECU reprogrammed by 2 different tuners for more power and higher RPM shifts. The car is faster but the problem still exists. I was convinced they fixed it with the later model valve body but when it happened again a few months ago, MBUSA threw in the towel and said they were not going to fix it. Their comment was something like "Only a very small number of cars are effected under very specific conditions and the event is not damaging nor unsafe". If enough of us keep complaining, maybe we'll finally get satisfaction.

BTW, I've tested the problem on loaners and other MBs and found that less than 10% have exhibited it consistently. In fact, my '00 CLK 430 has only done it once and it was on a downhill road which could have contributed.

c230_kS

hm....i did this when the car is at full stop and i have the car in 1st gear then full throttle without presing the button (the one u can step on on gas pedal..)let it shift into 2nd by itself, then it jerks