This is my old picture, work dont on corolla 2002-2008, vehicle here was running lean, would not become stable till next 5-6 minutes after starting and had no power during this time interval. everything was cross check, verified and on last was this one. i have pealed the wires, attached another set of wires with pealed wires, attacked multimeter where voltage was 1.20 Volts and slightly rotated and voltage started to increase and vehicle became stable at 1.38 Volts and then left it like this.
Range is 0-5Volts whereas once Voltage is high then vehicle runs rich and once its towards low side vehicle runs lean. comes set roughly at 1.35Volts from factory.
once work was completed, wires was sealed with sleeves. This is normally adjusted with exhaust analyzer, unfortunately none of the toyota motors in Pakistan had this basic piece of equipment. After searching a lot, found a post by someone where he advised me to do as what i did in absence of exhaust analyzer.
P.S: This is variable Resistor used for controlling Air to Fuel Mixture as corollas 2002 to 2008 does not comes with oxygen sensor and has a feed forward mechanism for controlling Air to fuel ratio rather then O2 sensor in late models corollas from 2008 to 2020.
Reference to old thread where i faced this issue.