leecavturbo

on idle ?????

wreckleford

iTrader: (2)

You either have to set idle to open loop or use Mrfred's wideband patch that uses the wideband for closed loop AFR. With this patch you can set the AFR in closed loop to whatever you want.

domyz

iTrader: (6)

mrfred's patch is only for IX. It hasn't been ported on VIII ROMS yet.

CDrinkH2O

iTrader: (7)

Some wide band controllers like the Zeitronics ZT-3 can simulate a narrow band output. If you wire the NB output from the controller into the front O2 input to the ECU, you can adjust the stoich (14.7 AFR) voltage set point in closed loop to move it either lean or rich.

leecavturbo

So that's the same as the narrow band as stock so how do you adjust set point in ecu?

CDrinkH2O

iTrader: (7)

I think you misunderstood me. If you use the ZT-3 with a wide band O2 sensor, you don't have to use the stock front narrow band voltage as an input to the ECU. Instead you can substitute the simulated narrow band output voltage from the ZT-3 controller. You then connect this output voltage to the ECU pin normally used for the front narrow band input.

A narrow band normally outputs 0.1 - 0.9V. It generates 0.5V at 14.7 AFR or "stoich". If the ECU sees 0.5V coming in on the front O2 NB input, it thinks everything is in balance and so doesn't start adjusting your trims.

The ZT-3 set point can be configured to output 0.5V for an AFR anywhere between 9.6 and 19.6. This "fools" the ECU into thinking that a lean AFR like 16.0 (for high mpg), or a rich AFR like 13.5 (so you can idle with big cams), is actually OK. There is no need to reprogram your ECU. In fact you can run it in closed loop and take advantage of the dynamic fuel trims like Mitsubishi intended.

Maybe you could tell us what you are trying to do so we can advise on the best approach?

leecavturbo

I know how simulated works and all that you posted but I didn't know the zt3 had adjustable set point.
So that's not adjusting anything in the ecu as I asked.
Exactly I have lumpy cams amongst other mods and wanted to play with afr at idle and stay closed

domyz

iTrader: (6)

I run my idle open loop at about 13,5 AFR and I have no problem at all. It eliminates lope MUCH more than adding 10* more advance at idle.
I don't see the problem with getting only the idle open loop.

It made the low trim drift a little bit, so I turned it off like you see in the HZ crossover table. From my testing it has the effect of LTFT staying at zero. I don't need it anyway.

leecavturbo

Cheers

ReaperX

iTrader: (5)

^ Agreed. In closed loop the only thing that will help the lope will be timing. With S2's I run open loop at idle, 13.7 afr and 15* timing. She purrs like a kitten with minimal lope.

domyz

iTrader: (6)

Yes, I'd say the timing mod has half the effect of this fueling mod for eliminating cam lope.

leecavturbo

Thanks all^

wreckleford

iTrader: (2)

I am using it on 96530006, it was ported over, I forget by who (sorry ), but you are correct in general.

domyz

iTrader: (6)

Nice, you are lucky. I think there is some functions that are not in the EDM that I need so I cannot switch to it

wreckleford

iTrader: (2)

I think Leecav could probably use it. I have converted a few 03 JDM 8s to 96530006 without any issues.

As you have said though, the open loop solution works just fine.