what else does the stock 02 sensor do other than try to maintain stoich? ive got my emanage ultimate installed now, but cant seem to find anyone having used the analog input and output to clamp the voltage of the stock o2- would this work and if not why not?


for the time being ive unplugged the stock o2 sensor and have sarted mapping my ignition timming (ive set my fueling quote rich for now till the timming is good.

my setup is

305 injectors
t25 turbo
emanage ultimate + 3bar sensor
fmic

and ive got det cans and a aem wideband ...

thanks in advance!

 

 

oh bugger, just realised i missed hte firs half off!

edit and corrected here

i need to know if i can just use the emanage ultimate to clamp the o2 sensor ???

 

Ok, it's been a few years since I've owned an EMU, and maybe they've changed this since then, but my recollection is that the problem with the analog output is that it only has one input variable, namely, the analog input.

It seems to me that the analog input & output were designed to allow you to rescale a sensor on its way to the ECU. So you can tell it that for an input of "x" you want an output of "y" (along a 1 dimensional table) however you cannot introduce a second variable (such as MAP) into the equation.

So you could run the NBO2 sensor through here and scale the table to prevent the signal from ever rising above, say, 0.6 volts, but that would prevent proper closed-loop operation from ever occurring- the ECU would go to max positive fuel trim and stay there all the time (and probably throw a code.)

We need to be able to allow the normal sensor signal to pass through to the ECU all the time, except when we are in a situation where we're deliberately adding positive fuel correction with the EMU. So to do that, we need an external switch, controlled by the EMU, which can select between the actual sensor output or a simulated voltage.

I did some searching and found this little writeup that I did a while back: https://www.miataturbo.net/showthrea...d=1#post204086

It describes the construction of a little external box which is controlled by the EMU's VTEC wire by way of the Aux Output Map.

 

thats some good info thanks dude, i have the latest version of the ultimate as far as im awear (version E) i think it was. But it looks like ill just make a clamp then. blocking the signal to 0.6 would probly just do the same as unplugging the sensor which is not really any good for trying to maintain economical driving and ease of mapping.

thanks again