Range Adjustment For Dual Analog EFIEs
Note: The range adjustment feature has been discontinued for other EFIE models. It has proven to cause more confusion in users, than it has been of use, and it's just not needed in a modern EFIE. However, our original Dual EFIE Deluxe and circuit board versions require calibration, and so we have retained the pots that can be used for range adjustment on these models only. This makes it possible to modify an EFIE for odd sensor types, such as the titanium dioxide sensor which uses a voltage range of 1 to 5 volts.
Follow these instructions carefully:
1) Adjust your EFIE to it's maximum setting. The quickest way to do this is to back off the adjustment screw until your meter reads below 50 millivolts or so. Then turn it clockwise 20 turns. The EFIE should settle out fo about .500 - .550 volts or so if its range was set at the factory. You'll need to do this procedure twice, once for each EFIE on the Dual EFIE board.
2) Open the EFIE's case and then see the photos below. Find the range adjustment potentiometers on your EFIE's circuit board. Note that the pots marked "Voltage Adjust" will not be found on the board for a Dual EFIE Deluxe. This is because the Deluxe version is adjusted by an external pot mounted on the case. For Deluxe models, the only pots on the board are range adjustment pots.
3) Turn the range adjustment potentiometer very slightly to increase the EFIE's voltage range. Note that very small adjustments to this pot make a large change to the EFIE's range. Also note that you will have to wait for some minutes to find out what the full result of your adjustment is due to the large capacitor in the circuit.
4) When your meter reads the voltage that you wish to have as the top end of your EFIE's range, then adjustment is done. Replace the back on the case.
5) Re-install the EFIE into your vehicle and be sure to adjust it, as it's currently set to it's new maximum value.