The components from Mouser arrived first today, so I soldered up one board after supper. I appreciate even more now, the surface mount placement equipment and reflow ovens at work! I didn’t have solder paste and hot air soldering equipment, so made do with a conventional iron with small tip and solder wire. Someone 1/3rd my age might have less trouble soldering U2. I worked under a cheap usb microscope that has quite an image delay....... With the IAT sensor removed from the bike & wired to the dongle, and a 2.15K resistor in series with the dongle to a 5v supply (to emulate the pull resistor in the ecu) I measured 3.46v for about 10s, then it drops to 2.55v. I didn’t have a thermometer at the table where I was working but it felt about 74F I’d guess. The TSTAT on the wall some distance away, showed 72F. At any rate, those measurements agree pretty well for what I was expecting at that temp. Those numbers equate I believe, to a simulated air temp lower than actual, by an amount to request 7-8% more fuel. Do you think for this dongle experiment, that 7-8% is enough? Or should I go big or go home...... I could change the onboard thermistors to a higher value resistance, to say double that amount.