The stock o2 sensor is a wideband - Toyota Yaris Forums

The Spectacle · 08-19-2011, 05:02 PM

I figure this is the best place to put this info. I won an aftermarket wideband in a contest and said screw it and installed it on the Yaris for s & g's. Few observations of note:

- 14.5-14.7 AFR is the cruising and idle target
- The o2 readings DO NOT oscillate during cruise. They reach the target and move .1-.2 points one way or the other to maintain the target. Narrowband sensors do not do this
- From what I can tell, the computer adjusts very fast and very accurately. Was very surprised to see this behavior
- Open loop WOT with the stock intake drops the AFR to 12.5 (rich). After installing my Injen CAI, the target raised to 13.1. Stock airbox is a major restriction on this car. Very noticeable difference between the two
- AFR richens up to a mind boggling 10.9 with the stock airbox right before and up to redline. With the intake its like 11.3 or so (I can't exactly remember, only did it once or twice)

From what I can tell, with just a proper standalone/piggyback computer this motor could easily pull 115-120whp with tuning and regular I/H/E upgrades.

auxmike · 08-19-2011, 09:16 PM

Did you use Scangage II?

YarisSedan · 08-19-2011, 09:45 PM

That could be because the yaris utilizes air fuel ratio sensors which is wide range. More expensive and more acurate. Where as oxygen sensor is more narrow range. The one after the cat is probally regular o2 sensor.

fnkngrv · 08-19-2011, 10:55 PM

We noticed this when I was attempting my first few tries at calibrating my FIC

The Spectacle · 08-19-2011, 11:11 PM

Quote:

Originally Posted by auxmike

Did you use Scangage II?

For monitoring all the stock sensors and gas mileage, yes. To monitor the wideband, I have a gauge

Quote:

Originally Posted by YarisSedan

That could be because the yaris utilizes air fuel ratio sensors which is wide range. More expensive and more acurate. Where as oxygen sensor is more narrow range. The one after the cat is probally regular o2 sensor.

Agreed. Primary o2 is wideband, secondary is narrow

Bluevitz-rs · 08-19-2011, 11:45 PM

Primary is not an O2 sensor, it's a A/F ratio sensor. But the secondary is an O2.

The Spectacle · 08-20-2011, 07:08 AM

Quote:

Originally Posted by Bluevitz-rs

Primary is not an O2 sensor, it's a A/F ratio sensor. But the secondary is an O2.

Edit: My Echo has 2 O2 sensors. That's what makes the Echo/Xb/Xa easier to tune. The computer is dumber than the Yaris.

What are you talking about? That makes absolutely no sense whatsoever.

thepartsmancometh · 08-20-2011, 10:01 AM

almost all newer toyota's use A/F sensors in the front position(2) and O2 after cat. The A/F's aren't exactly cheap, but they have their benefits.

Bluevitz-rs · 08-20-2011, 10:02 AM

I re-edited my post to be less confusing for you.

mazilla · 08-20-2011, 10:16 AM

Just to clear something up for myself...if the primary is A/F, why am I looking for a gauge with it's own sensor? Can I just run a gauge only and be done with that?

This is in regards to my turbo install coming up, gauges are all I need at this point.

Bluevitz-rs · 08-20-2011, 11:07 AM

from the original post that looks to be all that's needed.

The Spectacle · 08-20-2011, 12:04 PM

Quote:

Originally Posted by Bluevitz-rs

I re-edited my post to be less confusing for you.

Still confusing as all hell but I think I understand what you're trying to say. Both sensors are o2 sensors but only one has a range wide enough to read A/F, while the other can only read rich or lean. Most aftermarket wideband o2's are 0-5 volts and stock narrowbands 02's are 0-1 volts.

Quote:

Originally Posted by mazilla

Just to clear something up for myself...if the primary is A/F, why am I looking for a gauge with it's own sensor? Can I just run a gauge only and be done with that?

This is in regards to my turbo install coming up, gauges are all I need at this point.

I wouldn't mess with the stock o2. Who knows what the voltage ranges for that sensor are and how the ECU reads them. Your best bet is going the route I did, unless you can find a OBD2 reader than can pull A/F from the OB2 port.

I got my gauge from Prosport http://prosportgauges.com/

The Spectacle · 08-20-2011, 12:05 PM

To be 100% clear...I am not pulling my readings from the stock o2 sensor itself. My gauge is reading from an independent sensor that's installed near the stock o2 port on the header.

Bluevitz-rs · 08-20-2011, 12:56 PM

ok, I'll dumb it down as much as I can.

The first sensor in the exhaust located in the manifold is called an AIR/FUEL RATIO SENSOR. NOT AND OXYGEN SENSOR. The second sensor in the exhaust located after the catalytic converter IS call an Oxygen Sensor.

The job of the A/F Ratio Sensor is to adjust fuel delivery to maintain set parameters from the ECU. This a very fast and sensitive sensor.

The job of the Oxygen Sensor is to make sure the Catalytic Converter is doing it's job. This is a slow acting narrow range sensor.

The Yaris has a more sophisticated ECU compared to the Echo and can more accurately control fuel delivery based on more accurate readings from the AFR sensor.

ilikerice · 08-20-2011, 05:02 PM

Bluevitz is absolutely correct.

pre-cat is an Air/Fuel sensor. post-cat is the Oxygen sensor.

cali yaris · 08-20-2011, 06:27 PM

^ The first one is actually a hybrid design, but that's getting pretty nitpicky.

The Spectacle · 08-20-2011, 06:28 PM

No he's not. A/F sensors ARE o2 sensors! What the hell do you think the sensor is reading? Magic fairy dust?

You're arguing semantics with me and its making my head hurt.

ilikerice · 08-20-2011, 07:05 PM

Ok, I will agree there. Most people do refer to those sensors as O2. I was trained by toyota that they are a/f sensors. Which you are correct, is just a wideband O2 sensor.

So to get this thread back on topic. YES, toyota has been using a wideband O2 sensor for the past 15 years.

08-19-2011, 05:02 PM	#1
The Spectacle View User's Garage Drives: 08 BSP LB Join Date: Oct 2008 Location: Tampa, FL Posts: 218	The stock o2 sensor is a wideband I figure this is the best place to put this info. I won an aftermarket wideband in a contest and said screw it and installed it on the Yaris for s & g's. Few observations of note: - 14.5-14.7 AFR is the cruising and idle target - The o2 readings DO NOT oscillate during cruise. They reach the target and move .1-.2 points one way or the other to maintain the target. Narrowband sensors do not do this - From what I can tell, the computer adjusts very fast and very accurately. Was very surprised to see this behavior - Open loop WOT with the stock intake drops the AFR to 12.5 (rich). After installing my Injen CAI, the target raised to 13.1. Stock airbox is a major restriction on this car. Very noticeable difference between the two - AFR richens up to a mind boggling 10.9 with the stock airbox right before and up to redline. With the intake its like 11.3 or so (I can't exactly remember, only did it once or twice) From what I can tell, with just a proper standalone/piggyback computer this motor could easily pull 115-120whp with tuning and regular I/H/E upgrades. __________________

08-19-2011, 09:16 PM	#2
auxmike Drives: 2008 HB, A/T, Power W/L/M Join Date: Oct 2008 Location: LI, New Yawk Posts: 2,063	Did you use Scangage II? __________________ Never take eyes off opponent - Bruce Lee

08-19-2011, 09:45 PM	#3
YarisSedan Drives: 08 Yaris Sedan Join Date: Oct 2008 Location: California - Bay Area Posts: 2,773	That could be because the yaris utilizes air fuel ratio sensors which is wide range. More expensive and more acurate. Where as oxygen sensor is more narrow range. The one after the cat is probally regular o2 sensor. __________________ http://www.cardomain.com/ride/3210549

08-19-2011, 10:55 PM	#4
fnkngrv Mr. 155 and climbing View User's Garage Drives: Seriously Modded 07 Sedan Join Date: Jun 2006 Location: In The Hotbox Posts: 4,742	We noticed this when I was attempting my first few tries at calibrating my FIC __________________ Team Tiamat Racing on Facebook Youtube Channel: Team Tiamat Racing *Class record holder in Land Speed @ 154.5mph for 1.5 mile and 145.5mph in the mile in the F (2.016 to 3.014 L), G (1.524 to 2.015 L), and H (1.016 to 1.523 L) classes.*

08-19-2011, 11:45 PM	#6
Bluevitz-rs 1NZ-6spd View User's Garage Drives: '05 6-Spd Vitz RS Join Date: Oct 2008 Location: Oshawa, Ontario, Canada Posts: 2,967	Primary is not an O2 sensor, it's a A/F ratio sensor. But the secondary is an O2. Last edited by Bluevitz-rs; 08-20-2011 at 10:01 AM.

08-20-2011, 10:01 AM	#8
thepartsmancometh Drives: '08 LB, '07 WRX Join Date: Jan 2009 Location: midwest Posts: 187	almost all newer toyota's use A/F sensors in the front position(2) and O2 after cat. The A/F's aren't exactly cheap, but they have their benefits.

08-20-2011, 10:02 AM	#9
Bluevitz-rs 1NZ-6spd View User's Garage Drives: '05 6-Spd Vitz RS Join Date: Oct 2008 Location: Oshawa, Ontario, Canada Posts: 2,967	I re-edited my post to be less confusing for you.

08-20-2011, 10:16 AM	#10
mazilla advocatus diaboli Drives: 07 Yaris hatch Join Date: Mar 2011 Location: San Jacinto California Posts: 1,126	Just to clear something up for myself...if the primary is A/F, why am I looking for a gauge with it's own sensor? Can I just run a gauge only and be done with that? This is in regards to my turbo install coming up, gauges are all I need at this point. __________________ -Type 07 FFL- My odometer 03/11 http://i205.photobucket.com/albums/b...a/2843ed85.jpg

08-20-2011, 11:07 AM	#11
Bluevitz-rs 1NZ-6spd View User's Garage Drives: '05 6-Spd Vitz RS Join Date: Oct 2008 Location: Oshawa, Ontario, Canada Posts: 2,967	from the original post that looks to be all that's needed.

08-20-2011, 12:05 PM	#13
The Spectacle View User's Garage Drives: 08 BSP LB Join Date: Oct 2008 Location: Tampa, FL Posts: 218	To be 100% clear...I am not pulling my readings from the stock o2 sensor itself. My gauge is reading from an independent sensor that's installed near the stock o2 port on the header. __________________

08-20-2011, 12:56 PM	#14
Bluevitz-rs 1NZ-6spd View User's Garage Drives: '05 6-Spd Vitz RS Join Date: Oct 2008 Location: Oshawa, Ontario, Canada Posts: 2,967	ok, I'll dumb it down as much as I can. The first sensor in the exhaust located in the manifold is called an AIR/FUEL RATIO SENSOR. NOT AND OXYGEN SENSOR. The second sensor in the exhaust located after the catalytic converter IS call an Oxygen Sensor. The job of the A/F Ratio Sensor is to adjust fuel delivery to maintain set parameters from the ECU. This a very fast and sensitive sensor. The job of the Oxygen Sensor is to make sure the Catalytic Converter is doing it's job. This is a slow acting narrow range sensor. The Yaris has a more sophisticated ECU compared to the Echo and can more accurately control fuel delivery based on more accurate readings from the AFR sensor.

08-20-2011, 05:02 PM	#15
ilikerice Drives: 2010 black yaris Join Date: Oct 2010 Location: savannah, ga Posts: 2,868	Bluevitz is absolutely correct. pre-cat is an Air/Fuel sensor. post-cat is the Oxygen sensor.

08-20-2011, 06:27 PM	#16
cali yaris ULTIMATE View User's Garage Drives: 07 Yaris Turbo Join Date: May 2007 Location: Canoga Park, CA Posts: 14,859	^ The first one is actually a hybrid design, but that's getting pretty nitpicky. __________________ Micro Image forums, online store and shop are now closed. It was a great eight year run, but it was time to focus on other things. I'm still selling parts on eBay under micro*image seller ID and customers can still make requests for anything specific.

08-20-2011, 06:28 PM	#17
The Spectacle View User's Garage Drives: 08 BSP LB Join Date: Oct 2008 Location: Tampa, FL Posts: 218	No he's not. A/F sensors ARE o2 sensors! What the hell do you think the sensor is reading? Magic fairy dust? You're arguing semantics with me and its making my head hurt. __________________

08-20-2011, 07:05 PM	#18
ilikerice Drives: 2010 black yaris Join Date: Oct 2010 Location: savannah, ga Posts: 2,868	Ok, I will agree there. Most people do refer to those sensors as O2. I was trained by toyota that they are a/f sensors. Which you are correct, is just a wideband O2 sensor. So to get this thread back on topic. YES, toyota has been using a wideband O2 sensor for the past 15 years.

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