The thing on your Turbo is refered to as a, Circulating air safety valve. what you are looking at is probably what is left from the vacuum line that originally went to it. don`t worry about, just leave it as is, or pull the rubber hose off it.

Originally there was a vac line from it (item 71) to a switch over valve, (item 81) the SOV got vac off the main line from the Vac pump (item 67) to the brake Booster. a third line from the bottom of the SOV going to the VCV (item 65) on the IP.

Item # 80 is the Control Unit or also refered to as the Black box on the 85 300D and SD. the 84`s also had this unit. Item # 80 send a signal through a wire to trigger the SOV to dump some of the boost from the turbo, Item# 71, circulating air safty valve. or also refered to as the ARV valve.

The Black Box resides behind the Pass kick panel.

From a diagram in my FSM for the 617.95 engine.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works