The reason for doing this warm is that once warm the only job being done electrically is lambda control.
In the conditions you now describe, you are obviously removing the needed cold running enrichment. This lasts at most about 30 seconds or untill the o2 sensor starts producing current.
The EHA is the black cude on the side of the fuel distributor - single two pin connection. The idle air valve is also a two pin connection and the valve is in between some one inch ID rubber hoses on top of the intake behind the fuel dist (I think).
Bosch Master, ASE Master, L1
33 years MB technician