1 FMF

iTrader: (1)

been reading up on how tuning is done with wideband o2 sensors and using hptuners or efilive. My question is where do you install a wideband o2 sensor? For instance if I were to play around with my 2002 camaro does a wideband o2 sensor take the place of the oem pre-cat o2 sensors? If this is the does the wideband sensor send two outputs- the oem output signal to the pcm and then the wideband signal you use for tuning- so the pcm operates normally in closed loop? Or do you have to cut a hole in the exhaust pipe and weld in a bung to install the wideband o2 sensor if you still want to use your upstream oem o2 sensors when tuning?
I'm guessing both ways can be done, if so then what is the preferred/best method to get best tuning results?
thanks.

wait4me

iTrader: (10)

In EFIlive, make sure you take advantage of the serial input that it provides. It makes setup a breeze as far as integration into the scan tool. With the 0-5 volt only that some other companies have, it is a pain to make every type out there accurate all thru the scale, especially on the ends of the voltage range.
Serial= exact no matter what the scaling.

For the placement of the sensor, it depends on if you are doing a permanent or temp install. For temp, you can use the back rear o2 sensors, or the fronts, it just depends on how you are wanting to tune. "open loop or closed loop while tuning" If you run open loop, then it don't matter what you use. If you are doing a permanent install, then I suggest taking the bung that comes with your wideband kit and getting it welded in on the pipe somewhere in front of the cats.

1 FMF

iTrader: (1)

i was under the impression a wide band o2 sensor needed to be mounted before the catalytic converter to correctly report A/F ratio. Or does the chemical reaction in the catalytic converter not skew the A/F reading if the sensor is mounted after the cat ?

wait4me

iTrader: (10)

At full throttle If you put your dual wideband kit on the front o2 and one in the back, I see 0 difference. I check it often.

jimmyblue

iTrader: (11)

The cats won't do much to a WOT gas stream but at
lower throttle might jack the readings a bit if there's
HC/CO to use up the residual oxygen.

I got a separate bung welded into the I-pipe for next
to nothing, when I was having other work done.