Dogtag114

So for a few years now, if I start in only Sport from a dead stop and launch full throttle... the first gear hits redline and bounces off... then stutter stop shifts to second.

Honestly, I was in warranty, but afraid the dealer would reflash my car and suspected the previous owner had a tune since he did so many other mods so didn't want to risk losing it.

Now I am out of warranty and may still ignore it.... my questions are:

a. is this a transmission software thing or something a tune would fix?
b. is there anyway to know I have a tune already? (other than testing the speed limiter?) I did buy CPO... do they reflash the car for that or only inspections?

If I already have a free tune, I'll continue to ignore it... if a tune makes this beast even more enjoyable and fixes this annoying issue, I'm now tempted.

Jasonoff

Have you tried resetting the ECU's adaptive learning?
http://www.mercedesmedic.com/reset-m...-instructions/

I can't remember the thread, but it was confirmed write events are logged. Doesn't mean it's a tune though. So, if they're suspicious, they can investigate.

How much wheel spin are you getting? If a lot, I'd be willing guess WOT from a dead stop with limited grip will likely do that for everyone. RPM climbing too fast and you catch the rev limiter before the shift to 2nd.

tphss

From my understanding none of the common tuning software (Eurocharged etc) have anything to do with the transmission. You can however reset your TCU, I did it yesterday and it might help you too, see this:
https://mbworld.org/how-tos/a/merced...and-tcu-388898

604 C63

Particularly with that transmission. Sure miss the "rubber band sling shot" feel that came with the torque convertor tho.

Dogtag114

I have done the TCU reset procedure before... Thx. Have tried for a while but recall it did not change it.

Dogtag114

Tiny wheel spin on launch but full traction for the top end of first guy before the shift miss... I'll see if I can find a creative way to video the tach...

Jasonoff

That's not right then. How many miles on it? Which trans is it?

Delayed engagement is a sign of pressure problems.

Dogtag114

2009 stock tranny as far as I know.

Had this issue at least three years now... If tune would address it, it might push me over the edge...

roadtalontsi

its more than likely tune related. no they typically dont do reflashed during cpo. the tune doesnt change the transmission however it changes the torque output and request to the transmission which does change the way it shifts.

Jasonoff

Have you had the trans fluid done?