EDC on 95 300tdi auto

Wanted to drop the tickover a tad on my auto yesterday,but on inspection its an EDC model with fly by wire accellerator and no direct mechanical link to tweak.
How does one go about this?Theres a multipin under the dash that I spose is the access for a confuser.....any thoughts from the panel?

One doesnt - the ecu controls idle speed.If its too high then one possibility is that the coolant temp sensor has gone open circuit.This will raise the idle and advance pump timing making the engine sound harsh too.Mine suffered this,when I stuck it on Testbook it showed coolant temp as about -90c.When I lifted up the acoustic hood to look at the temp sensor the engine slowed down and sounded better - looked at Testbook and it read about 85c.Throw the hood away,job done.

THANKS 8!Being thick can you tell me where the sensor and hood are located?