Just an FYI about Spartan. It is problematic with ME7.1 for some reason.
Mine measured voltage wise as follows when there was nothing hooked up to it:
no oxygen (sensor in a zip lock bag (watch out it gets hot fast!) with butane torch with open valve, not lit naturally): 0.005V
open air: 5.01V
So it is perfect. Even Zeitronix didn't do as well with 5.05V on high side.
Now the "fun" starts. ECU in disconnected O2 plug state has 0.45V potential on signal wire... no idea why and it is the case on both plugs. Once you connect Spartan to signal wire of ECU, something happens...
The "10.00" AFR (rich, butane gas) that was previously 0.005V reads on voltmeter and in ECU via Me7 Logger as 0.053713V (that's 0.12AFR if you were using 2AFR/V function Spartan is scaled at)
The "20.00" AFR (open air) that was 5.01V reads as 4.424V... So it is only 4.424 * 2 + 10 = 18.848 AFR if you were using default scaling. 18.8AFR reported in logger is a long way off from 20.00...
Zeitronix in the same scenario holds the voltages regardless of open end or ECU hanging on the other side
So... I mathematically arrived at a function that uses the new limited voltage range and re-scales V/AFR ratio, it should work as it proved to calculate 14.7 AFR voltage level to what I measured via ECU when idling. I will post proper factor and offset in a day or two once I log the car and prove that conversions work right in ME7 Logger.
In retrospect I regret not getting second ZT-2, it is overall better unit IMHO. As is, the spartan logic board is essentially hanging right over the exhaust area as it is incorporated into the O2 WB plug receptacle... The sensor cable is short preventing me from placing the plug part in safe environment. I wonder how long will that live. ZT uses the same Bosch LSU 4.2 sensor but the sensor plugs into long reinforced extension cable that runs up to dashboard area through ECU box and it is here where all the electronic live. I've had zero issues with zeitronix for last three or so years.
I am perplexed why didn't they simply put the same board on the other side, or made a separate cable with pig tail on it, of cable - it wouldn't be exposed to brutal near exhaust area. The current set up almost forces you to spend extra money for oxygen sensor cable extender, long one at that, you know the one that costs $60 at least.... oh wait, now this whole thing is almost as much as ZT-2 with quite a few features missing from it, it is still a little dumb board without connectivity and ability to be programmed for different narrowband switching point for example...
