I realize maybe I don't?

When I got my 82 240D and was new to the w123 it would at shift super high engine speeds and very hard. After immersing myself in the vacuum system I realized it had multiple leaks.

Over the corse of the past year I have replaced the major components in transmission related vacuum shift controls. I have NO leaks in the system or anywhere else either.

- Brand new OEM modulator

- Two brand new OEM switchover valves on the valve cover

- All new lines and fittings

- Tested and adjusted the VCV

- disconnected the EGR

And my transmission still doesn't shift the way I think it should.

Fluid and Filter have about 15k miles on them.

Symptoms:

When cold Shifts are soft but abruptly in gears 1-3. The 3-4 shift is very slow and soft. It doesnt flare or slip and actually shifts better if I run it up til about 35/40 and then let off the throttle. If I just leisurely take off it will shift super slow from 3-4 around 25/30 mph and really mushy.

When warm Shifts are abrupt and quick at low/partial throttle. Full throttle produces super smooth quick shifts but I think the shift points are off. 1-2 shift with the kick down switch activated is 15mph. 2-3 with kick down is 28 mph, 3-4 around 45mph.

Today I realized leaving the shifter in L that the car would shift into second gear at about 20mph! So I'm thinking I must not have the system adjusted correctly if it will make it to 20mph in L but only to about 13/15mph with the kick down switch activated in D.

Should I crank the modulator pressure up a smidge?

I've run the car through the gears with the vacuum line heading to the trans disconnected and it still shifts early to me. My intention isn't to always be winding the motor out but I suspect it is shifting SUPER early at partial throttle making the car a real slug.

Whew sorry for the long post. Any help would be appreciated. I am determined to get this thing to shift correctly!

Does this car have a bowden cable aka "Control pressure" cable? If so, tighten it up, that'll raise your shift points.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

The shift "schedule" varies with gear selection, by design.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

No it does not. All the shifting is controlled by vacuum. WHY. My w116 that has shifting controlled completed by a pressure control rod is so much simpler to adjust and shifts just fine. You would think they would have kept the 240D simpler.

ma:

Which side of the trans is the vacuum modulator on?

Passenger side

ma:

Assuming that you are not in England (and some others), then "passenger" = right side.
Unusual for a 1982 car, but not impossible that the modulator is on the right side. Hence, a 722.117, which is indeed that unfortunate attempt by MB to use vacuum only control. The key to it all is 1) the initial setting of the adjustment screw inside the modulator, and 2) adjustment of the vacuum control valve(s) that are operated by the throttle linkage.

For anyone reading this I increased the modulator pressure and re-adjusted the VCV and trans now shifts much better.

Could you if you can please explain how you did that ? Thanks