To your question on audizine regarding testing the sensors with a multimeter:
It's not possible to do that. The sensor is a Typ N thermocouple. It is usually not the thermocouple that fails but the sensor electronics. The signal for the ECU is a 100Hz PWM that is varried between 945-1050
Really interesting thought, so the GM flex fuel sensors work by outputting a 50-150hz signal depending on the ethanol content (50hz=0%, 150hz=100%). Currently, there is only the Zeitronix ethanol content analyzer, which is $200 and requires a seperate GM flex fuel sensor. Do you think there might be a way to hook up the GM flex fuel sensor to the EGT input on the ECU, possibly change the scale of what the Hz mean in the map on the ECU, and be able to log the ethanol content via ECUx rather than having to buy that separate Zeitronix gauge? Electrical engineer's thoughts?
I have no idea if that would work, but if so I would think the pro wouldn't be EcuX logging. If that could work then I don't see why you wouldn't be able to base fueling on ethanol content.
For sure...if you can figure out how to get those map to correctly affect the fueling, etc.
I was thinking about it though, and for my purposes (checking ethanol content every gas tank), I wouldn't want to have to log with a computer anyways. So I think I'm going a different route with that sensor just to check the content. Would be sick to figure out how to make it true flex fuel though!
