What's the name of the cable that controls emissions?
 

It's for my 1994 E320. Does anyone know the name of the cable that goes from the transmission to a vacuum diaphragm of some kind? It's supposed to cause the transmission to shift a little sooner so that it cuts down on emissions. Where does it go? From where to where? Thanks.

You're thinking about the upshift delay cable. When cold, it holds it in lower gears longer to heat up the engine sooner. It goes from the throttle linkages into the trans.

Yes, that's what it's called. Thank you. Do you have any idea what the name of the small electro/vacuum device is just behind the brake booster? I believe that also has something to do with emissions/causing a check engine light to illuminate. This little device is surrounded by a brass colored piece of metal, like a holder it sits in. It has a teal green vacuum line that leaves it and disappears downwards by the oil filter. Any idea what that small device is called?

We're getting these bizarre phantom codes that don't make sense (I hate OBD I). My friend brought the E320 to an independent mechanic who said the CEL was either caused by this cable or the small device behind the brake booster. At least that's what his code reader told him.

That is a vacuum switchover valve. When activated it allows vacuum to the upshift delay cable which in turn delays the upshift. It should only be active up to 60 degrees C, after which the car should shift normally. If you put vacuum on the green vacuum line going down to the cable, it should hold, if it leaks the cable is bad. You can also apply power and ground to the pins of the valve, it should switch with a small click and allow vacuum to pass when active.