Need Guidance.. Transmission.. Overload?

Some further thoughts while I'm at it.
The Vacuum valve on the IP has a nice linier movement on the vacuum gauge. There's only about 15 inches of
vac on the modulator at idle, about 5 with slack taken up, and about that till it goes to zero at full throttle. Odd that 5 inches is enough to make it shift so loose. I hooked the trans modulator directly and solely to the IP's vacuum regulator and saw much more vacuum, but the result on a test drive was about the same. Need to replace those two switchover valves. I pulled the modulator line off again after another drive this morning, it's solid as a rock again. I'm going to leave it that way unless someone tells me I really should jack the line preasure up. It's lasted this long.
Another question. The 83 300D has only the engine overload protection, not the engine/trans overload setup, correct? Manual states that the vent valve on the firewall by the booster vents at a given boost which is fine, tested and works, it also says it vents the ALDA in sudden off throttle situations so the residual boost isnt moveing more fuel when it's not needed. Question is how in heck does it manage this? Either the manual is vague or I missed something. There's even a vac/elec diagram that shows nothing but the fused power source and the switched ground from the intake sensor, but the manual also reads like there should be the off throttle venting ability there somehow. ??
Lastly, is this model suposed to do the 2nd gear start deal? Mine seems to not do this, unless it shifts from 1-2 pretty inperceptably, which is unlikely.
Thanks a bunch..
Rex 83 300D
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What manual claims that the ALDA is vented in a sudden off throttle action? The ALDA is vented only when the boost pressure exceeds 16 psi. That's to prevent a run away engine situation if the wastegate were to stick shut.
The transmission is set to be in 2nd while at idle with the brakes applied (to prevent creeping) and to downshift - almost imperceptibly - the moment that you release the brakes and step on the accelerator.
The transmission is a 4 speed. 1st is manually engaged by shifting into L at a full stop. Start off in 1st, upshift to S and immediately shift back to L to hold 2nd gear, then back to S for third and D for 4th. And this way you can check whether its automatic shifts are as they should be.
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Unless I'm completly reading it wrong, the grey cover factory service manuals are where I'm getting my info from. And a printout from one of the MB tech sites online. I'll double check specifics. I don't see any way for the system to do anything other than vent overboost my self. Though the idea of cutting extra fueling immediatly at off throttle isnt a bad one I guess.
Rex

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