Was the high tech infrared reading taken at the EXACT same location of your sensor?? Dont know about the spectrum sensor, but my React sensor is mounted on the lower fin on the back side of the engine a good 1/2-3/4 of an inch away from the typical temp gun measure spot the glow plug. Will my temp reading match a temp gun reading taken at the glow plug?? Not likely. Is my sensor reading less accurate than the temp gun reading? Definitely not, just different because of the sensor location. This gets back to my original post about interpreting what the readings are telling you. You have to tie the numbers your getting to what your car is doing whether you use a temp gun or telemetry. My numbers I use will be different because I'm taking all my readings from one consistent location that is a half inch removed from where the temp gun readings are taken. I get people all the time that pick my car up and hit with a temp gun and want to start twisting screws on it. I plead with them do not touch it, my temp is fine.