wide band wiring into stock ecu

Right as alot of people mat know that wideband o2 sensors can simulate a narrow band ( i didnt know this till recently)

the question is how would you wire that back into the stock ecu ?

would you disconect the stock lambda at the plug inthe bay fit your wideband run the wires into the cab and cut the old ox1 Main o2 heated o2 feed and wire in your signal from the simulated wideband? any information would be great.

http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13918&d=1112558155

I intercepted mine at the ECU. FWIR I think its pin 48 and i just used an ECU earth.

although IMO there is no advantage using it over the std sensor, unless you need to replace it.

dam how did i miss that reply doh!

thanks rick what i was after doing is just not having another o2 in the down pipe and what i will be doing is putting it through a relay that my aem fic can switch off the signal going to the stock ecu to force it into open loop at 0.1 bar or what ever i set kit at in the fic

does the afr guage still act as noral with displaying the afr?

You cannot force the ECU into open loop by switching off the lambda signal, the ECU will still expect the signal, therefore it will respond by throwing a fault, and running things rich, the only way you can force open loop is to make the ECU see a false MAP or MFA signal, depending on what its running.

i have been reading up on supraforums that a few of them are doing this with sucksess by just cutting the o2 signal, its the same as unplugging the o2 sensor, hope this link works lol

http://www.94supra.com/misc/o2-sensor.wmv

As i said the std ECU will just default to running rich, when there is no lambda signal detected, i don't see any point in running so rich at idle or during closed loop,

what are you trying toachievee?

don'tnt see the point, as the std engine can make + boost from as little as 1,800 RPM with the right loading.

i should say im going to be finishing the single conversion the weekend and with the stock gte ecu runing boost at 0.5 at part throttle will be way to lean at stoich (closed loop) im trying to force the stock ecu to open loop so i can adjust the fuel map with the fic i have.but still keep it in closed loop for idle and normal driving up to say 0.1 bar then switch it

there are other ways to do this but screwing to o2 feed back but i read this was the easiest way.

do you have any pointers on what to do or how to stop it making that sort of boost and still keeping 14.7 strange that toyota would let it make that much boost stock anyway to me

As far as i can see in my E85 map on the Emanage the stock ECU goes into open loop at 0.1-0.15bar at least that's where i change the fuelling and it works fine

i have watch mine go from where i was adding fuel say 13's and the stock ecu triming out and putting it back to 14.7 up until 0.5 part/light throttle,

i dont know if that will cause damage with part throttle but dont like it just seems way lean for that sort of boost.

I'm afraid i still don't see what the problem is? there is no need to change the fueling beyond what the STD ECU runs, when there is no + pressure, and the ECU will be in open loop once the turbo is making boost, there is also an RPM threshold for open loop,

so if your running a single, there will be no need to try and force open loop as boost will be after the std pressurethresholdd, cant quite remember what the RPMthresholdd is but i suspect you should have no problems.

I also ran EMU on my single and had no problems, part and transitional throttle are always harder to set up with piggybacks, depends which one, but shouldn't require forcing open loop, surprising just how lean you can run with low boost/load, if its setup properly.

so a t67 at part throttle making 0.5 bar of boost at 14.7 afr if safe ?

so a t67 at part throttle making 0.5 bar of boost at 14.7 afr if safe ?

I'm not saying that, i am saying that you shouldn't even need to force the ECU into open loop at 05 bar,

what are you usinging to log these results? it sounds like your just looking at averages on the logs?

its very easy to see scary AFRs etc depending how the logging is setup, especially during transitional throttle.

I'm not saying that, i am saying that you shouldn't even need to force the ECU into open loop at 05 bar,

what are you usinging to log these results? it sounds like your just looking at averages on the logs?

its very easy to see scary AFRs etc depending how the logging is setup, especially during transitional throttle.

sorry i have not logged any of it this was when my car was hybrid while driving i could see it through my afr guage and boost guage , this would only do it when very slowly accelerating but that was the max i saw.

the stock ecu goes open loop at 0.5 from what i could tell. is that normal

sorry i think the goal here is to stop the stock ecu trimming out my maps,

One thing to remember is that there will quite often be a difference between the actual engine MAP sensor reading to the boost gauge reading, as they are quite often calibrated differently, especially the cheaper ones, if i can find them, i have logs of both std MAP and Greddy MAP and both are different, and boost gauge read different to both!

Its also dam near impossible to be 100% sure that you have seen the correct correlated readings when your trying to watch the RPM boost and AFR wile trying to drive

The RPM Threshold is at 4000 where the ECU switches permanently to Open Loop regardless of Boost.

After my testing with E85 i honestly can't see much of a problem with the stock ECU in closed loop even with a single Turbo. When i first went for 100% E85 the fueling was at 16AFR and it took a while but it adjusted the fuel accordingly to 14,7. I would worry about getting the open loop correct

Other than that i noticed with pump fuel(and stock JSPEC twins) that the ECU trims the fueling to 14,7 almost all the time apart from open loop so it can't be that wrong if Toyota programmed it that way

thanks guys but i think im gonna screw the 02 to knock that 14.7 down to about 13 above 0.2 bar while building boost even if it is part throttle closed loop, and as soon as its open loop i will have full control and get it into 11s. then give it to the mapper to see what he says

right dont waste your time and try doing this with a aem afr it even says on there site that most ecus dont like there simulation of the narrow band, once i found after doing it for a couple of hours

I never had a problem with using a simulated NB O2 from Innovate WB with my std ECU, even when messing with adjusted NB signal, its only a 0.2-0.9 volt signal just like std sensor, don't know why the AEM WB sim should be any different.

beacause anything aem is poor you would think it would be easy

this is from a aem administrator

The 30-4100 has the option to emulate a narrowband sensor however most OEM ECU's don't like this simulated sensor reading if that happens to be what you're wondering

and this

You can try and simulate the narrowband signal going to your stock ECM but it may not like it. You'll want to use P4 to simulate a standard narrowband O2 sensor signal. Every car is different and some have been okay and some haven't. Your best bet is let the stock narrowband sensor talk to the ECM and use the UEGO separately to display AFR.

Makes no sense to me, like i said its purely a straight voltage signal, unless the AEM is incapable of keeping the voltage withing the ECUs expected parameters, which is sounding likely, going by what there saying, so if thats the case why do they bother with the NB output?

but the narrow band is not a straight voltage the wideband is the narrrow pulses between 0.3 and 0.7 to give the correct figure, i think its the length of the pulse that they cant get right they come out with something like it has a signiture of the signal, the reason they say it has the feature is to sell it as i might work on 1 car,

the aem fic and aem afr gauge work but if you want them to run all there features you must be very lucky, i think they have tried to work with a wide variaty of sensors and ecus etc but toyota and subaru seem the worst hit, i cant even belive that this stuff was promoted on the forum at one point for small singles on the supra

You have it around the wrong way, the pulse that you see from a lambda sensor is in response to the ECU changing the fueling from rich to lean, in order to try and keep the fueling to stoic, when people say an o2 sensor is dead stuck at one voltage, or responding slowly, its just its response to the changing fueling from the ECU thats failing.

An O2 sensor does not pulse naturally, if you look at an O2 sensor behavior when you are accelerating it will show just rich and vice versa for closed throttle, no pulse.

i stand corrected then

but that proves my point even more that anything aem is complete poo