Need Info On A Goodman Gus 075-3 Older 90% Furnace

haank

the hsi ignition module on this goodman GUS075-3 is a united technologies series 18 that comes as oem component on this 1st generation (I think) 90% gas furnace. Anyway it turns the hsi on & off and also senses the flame thru flame rectification (I assume) but I have installed a new flame rod made specifically for this furnace and the gas valve only opens for 8-10 seconds so I assume there is aflame sense problem. I also replaced the wiring from the rod to the module yet I show less than .% micro amps and also there is no ac voltage on the rod after the valve opens. I guess the module is condemnable but I keep thinking I am overlooking something> I vaguely remember having to deal with this Utech module years ago and it had different specs & characteristics than a common integrated furnace printed circuit control board ? Am I crazy ,memory impaired or just being paranoid?
Please help- any feedback would be appreciated