W202 shift pattern adjustable by dealer? - PeachParts Mercedes-Benz Forum

hk20000 · #1 01-30-2007, 09:58 PM

After hearing so many stories from my friends who own VAG vehicles it makes me wonder this: Is the dealer capable of reprogramming your shifter program so you get softer/sharper shifts? The C220 I'm driving shifts like I'm shifting - in a race car probably - so it's pretty harsh for city driving.

Is it fuzzy logic have I been driving the car too hard lately and cause the computer to think I want it to shift as quickly as possible? If it's fuzzy logic can I or the dealer make it reset and start learning from scratch so I can slow down the shifts?

searched but most threads are for 80s Mercedes.... thanks.

deanyel · #2 01-30-2007, 10:23 PM

The dealer could do it, or you could do it, by adjusting the vacuum modulator on the side of the transmission.

xvvvz · #3 01-30-2007, 11:21 PM

When was the last time you changed the transmission fluid? Even though the trannys were supposed to be life-time sealed, most people are advising to change the fluid somewhere in the every 30-60k range.

If you want to reset things, what about trying the 10 minute battery disconnect routine? Have your radio code handy and read up in the manual on resetting the windows and sunroof.

TMAllison · #4 01-30-2007, 11:37 PM

Your post doesnt say what year yours is....the below procedure works on my 99 W210 with a 722.6 trans.

1. Turn the ignition key to the on (not start) position.

2. Press the gas pedal to the floor and hold for five seconds.

3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.

4. Wait at least two minutes for ECU to reset.

deanyel · #5 01-31-2007, 10:16 AM

It would be nice to know what it is, but a C220 is always a 722.4, at least in the U.S.

hk20000 · #6 01-31-2007, 06:01 PM

got more detail on that vacuum modulator tuning? I don't think my transmission got fuzzy logic it turns out.

thanks.

deanyel · #7 01-31-2007, 06:52 PM

Try a search, and/or this:

http://www.mercedesdismantlers.com/722.3and722.416_transmission_adjustments.html

cool · #8 01-31-2007, 10:55 PM

if your not familiar with how to adjust the vacuum modulator, I suggest you bring it to a garage who knows, to avoid getting worst result.
If your knowlegable with the shifting cable (located on the engine compartment) I would suggest check for a moderate slack on that cable first before you proceed to adjust the transmission vacuum modulator. (in adjsuting the modulator you would need a pressure guage plus data for your tranmission.

hk20000 · #9 02-01-2007, 10:25 AM

From the dismantler's page it looks as though it's just a seat of the pants kind of tuning??

That first picture in the dismantler's website is so small I can't make out where that blue cap thing is located? On the transmission? or under the hood?

I wouldn't think the cable would be the issue then? Coz it shifts at the right time, just shifting really really hard....

hk20000 · #10 02-02-2007, 02:32 PM

broke out the trusty hydraulic jack and went under the car....

the white pvc tube is off the transmission.....errr yeah.

So shoved it back into the rubber tube and all is well.

deanyel · #11 02-02-2007, 03:20 PM

For future reference the vacuum modulator is on the driver's side of the transmission. You may have to jack up the car a couple of times but it can be sort of a seat of the pants operation - play with until it feels right.

xvvvz · #12 02-02-2007, 05:34 PM

>>the white pvc tube is off the transmission.....errr yeah.<<

"Cinderella story" to be sure! Gotta' love a simple fix.

hk20000 · #13 02-02-2007, 09:48 PM

I also noticed fixing this fixed my no-cruise control issue. The cruise control was probably acting up because it couldn't get an accurate vacuum reading from the engine.

I'm so happy everything is in good shape now.

I just need to maybe replace the signal stalk for flash function and all my new (to me) benz problems are solved.
thanks everyone for their help!!!