Hey......how does the 86 190E control the change in temp (amount) of coolant to the heater? There is what appears to be a small electric motor/valve on the left side of the engine compartment w/heater hose going to it. Two wires go in to it as well, if this is the bugger, does one wire increase the water flow and the other one decrease it? If so, how can you test it? How much voltage is used to move it and where does it get its signal? Thanks!!!!