krackle82

Will a wideband o2 sensor work, or give any gains in an oe ecm with oe tune?

Six_Shooter

iTrader: (2)

There are no gains to be found using a WBO2 sensor to be used only to feed a signal to an ECM.

The OEM ECM can only use a NBO2 signal, that being 0 to 1V on a very non linear scale, it's more like a switch, than a sensor range.

Most WBO2 sensors include a simulated NBO2 output that can be used when it physically replaces the NBO2 sensor.

krackle82

Awesome, thanks.

Orr89RocZ

iTrader: (20)

If you had a 730 ecm and ran code $59 in one or two bar map mode, you could use wideband in closed loop. No real benefit but possible

efiguy

iTrader: (2)

I'm not sure how a wideband wouldn't be beneficial. It would allow you to better tune wot and other parts wouldn't it? If the ECM is tuneable then you now can get actual wot air/fuels and can adjust accordingly.
And most narrow band O2's aren't overly accurate beyond 14.5-14.7 anyway.

I'd see this as a win-win. Do I have bad info?

Orr89RocZ

iTrader: (20)

I think what he means is, if you run wideband signal to ecm to monitor air fuel, its no real different than using a separate gauge kit, especially one that can log air fuel vs rpm.

However having stock ecm log air fuel along with all the other important parameters i find very helpful. You can add wideband to datalog stream in these stock ecms. I just remembered there was a way to add it to 165 ecm for maf guys.

But i have tuned based on a wideband and never logged the car using stock ecm. Just tuned by watching tach, o2 gauge, and ecm screen output but never recorded it.

EagleMark

Yes! Narrow bands are accurate at Stoich of fuel and have nothing to do with AFR.

Wide Band controllers are not AFR, they are Lambda, Lambda is calculated to AFR depending on what you set it to.

If you set it to 14.7 it will read 14.7 at Stoich/Lambda, even if you are using E fuel which would be 14.2ish. Lambda is always correct, AFR is only close if you set the controller properly to the fuel used.

krackle82

Ok, so wbo2 good for fuel tuning, not so good as a direct replacement for nb02, in a stock ecm set-up. Thats the general consensus, yes?

Ronny

iTrader: (1)

The GM ECU is looking for a signal from the NB 02 sensor.

This is taken fro RR's paper:

"The proportional PID term starts with the O2 sensor reading, and ends
with a correction to the final calculated PW. The PID proportional term
always works in the opposite direction of the immediate rich/lean O2
sensor reading.
The purpose of the PID proportional controller term is twofold. First,
it is used to attain the desired AFR quickly. Second, it is used to
maintain the switching of the O2 sensor about the desired AFR point.
The PID controller term starts with the O2 Error Term. This is the
amplitude of error (or difference), between the O2 sensor and the
desired O2. This value is used as a lookup index for the actual
proportional error term.
The combination of the proportional term and the INT term is referred
to as the closed loop correction term (CLT). When in open loop, neither
the proportional term or the INT term as used.
There are two filtered O2 sensor values kept by the ECM. One is a fast
filtered value that follows the changing O2 sensor reading closely. The
second is a slow filtered value that lags the changing O2 sensor reading."
end...

When you substiture the WB for the NB it needs to provide a signal that the ECU can interpret. Signal needs and smells to be that of a NB.

I see no advantage.

WOT is calc'd off a desired A/F based on last BLM seen as well as CID injector flow and fuell pressure. Stock ECU cannot interpret a 12.5/1 A/F that WB witnesses.

WB is a great tuning tool to verify what the engine is seeing.

Afterrmarket ECU is a diff story.

If one was retro fitting a carbed car to EFI and using a stock GM ECU it might be of a convenience to use one WB sensor

krackle82

Not just an answer, but an explanation why. Thanks Ronny.