Bad Air/ Fuel mixture sensor warning for ALL Yaris owners - Page 2 - Toyota Yaris Forums

TheSilkySmooth · 11-17-2008, 01:55 PM

A zero-to-5 V is a wide range Lambda (mixture) sensor which is still technically an oxygen sensor. It just has the ability to read lean and rich conditions which a std O2 can only read (perform a step function form near zero volt output to 1+v output at rich) so the EC unit can run at stoichiometric or "perfect mixture". The Car swith the old system are constantly varying between lean and rich to find the centre. On the 0-5V, Toyota can then run the car a bit lean at light / throttle light load. This is like what a dyno tune shop uses for a sensor. They Used to be big bucks and I though aonly used on the Prius - but the tech must have trickeled down the inexpensive Yaris. Now the mystery of the awesome gas mileage (with my dad driving at least) is solved! Yeah, dad gets 40 and sis gets 35!

sonja's bro (Our family, we got to get separate logins! but we love the Yaris World!)

kou · 11-17-2008, 02:05 PM

any time you have to change an o2 sensor i have found you should heat the area of the pipe/manifold around it,this usualy gets even the rusted ones out.

Return of the Yarii · 11-17-2008, 07:26 PM

I have an 07 Sedan and mine was crossthreaded, found out when I did DC header install, bought a new one from Ken @ Sparks. Its listed in the classifieds along w/the header.

It is indeed an Air/Fuel Sensor, the O2 sensor is downstream

*pending sale of A/F Sensor to member on the board*

TheSilkySmooth · 11-18-2008, 09:24 AM

Quote:

Originally Posted by Return of the Yarii

I have an 07 Sedan and mine was crossthreaded, found out when I did DC header install, bought a new one from Ken @ Sparks. Its listed in the classifieds along w/the header.

It is indeed an Air/Fuel Sensor, the O2 sensor is downstream

*pending sale of A/F Sensor to member on the board*

The is all just a matter of semantics but these sensors conduct OXYGEN at various mixtures outputting a voltage in response to the mixture, so the sensor ONLY senses oxygen but the EC can calculate the mixture using E and a couple other variables for cross check. There is no FUEL sensor on a car per se. You have the MAF that indirectly "supposes" air flow through the "cooling" effect of ambient air running over a hot wire "conductor" or foil and adjust voltage across to run in stasis, and MAP that supposes "throttle position" by the reading absolute pressure in the intake manifold typically with a mechanical device sim to a "barometer". Toyota service parts can call it what they want, but the engineers that design it call it a wide band o2 sensor that looks at free oxygen in the pre-catalysis effluent stream. So maybe we call it #1?

TheSilkySmooth · 11-18-2008, 09:35 AM

And NOW, to put me in the running for the big dick head award: The auto repair industry recognises MIL* for what we've been calling a CEL. I know this is "Down wid teh MANg Age" but very soon if not now NO ONE will know what anybody is talking about if we all make up our own terms for stuff and do not use the proper term.

*MIL = malfunction indicator lamp

White Cholera Woiker

eric81 · 11-18-2008, 12:01 PM

The Silky Smooth is far too smart to be from earth. We have aliens. Anyone got any Raid? Anyone? And what exactly does that mean anyways? The Silky Smooth... what is so silky smooth? I don't understand?

Still, crossthreaded A?F sensors suck, and they keep us from being able to use our aftermarket parts without replacing a bunch of other stuff. I also recommend checking the little silver bolts on the top of your engine that hold the spark plugs in place (they are black, have one bolt in them, and there are four of them across the top of the engine) to see if their bolts are as bad as mine were. They used a cheap bolt on mine and I snapped it in half trying to put it back in place. I took a different one out to measure it at the hardware store, and it was all stretched and warped too. So I replaced them all, and they were all bad. Toyota sure did save those pennies when it came to our cars.

TheSilkySmooth · 11-21-2008, 01:35 PM

Quote:

Originally Posted by eric81

The Silky Smooth is far too smart to be from earth. We have aliens. Anyone got any Raid? Anyone? And what exactly does that mean anyways? The Silky Smooth... what is so silky smooth? I don't understand?

Still, crossthreaded A?F sensors suck, and they keep us from being able to use our aftermarket parts without replacing a bunch of other stuff. I also recommend checking the little silver bolts on the top of your engine that hold the spark plugs in place (they are black, have one bolt in them, and there are four of them across the top of the engine) to see if their bolts are as bad as mine were. They used a cheap bolt on mine and I snapped it in half trying to put it back in place. I took a different one out to measure it at the hardware store, and it was all stretched and warped too. So I replaced them all, and they were all bad. Toyota sure did save those pennies when it came to our cars.

This is typical Asian practice, see it a lot on street bikes - its called "torque to Yield" the bolt is not reusable and permanently strained out of shape. It keeps the fasteners from coming loose. Unlike GM whom has all kind of problems with "oversized" bolts coming loose on intake manifolds because they are under-torqued and back off over time. SAves on washers also which are a bitch to handle in assembly lines.

TheSilkySmooth · 11-19-2008, 01:53 PM

I am the silky smooth brother , not the silky smooth.

I wouldn't think the factory would cross thread the sensor - maybe it was fused to the bung on purpose? Does any tech on here know if the header sensor comes together as one part#?

This is all basic stuff if you are a tech or read tuner mags and forums a lot. Gotta get out there and Ed-U-Kate yosef

TheSilkySmooth · 11-19-2008, 01:58 PM

Thread Hijack
Any one pulling off the headers - can you tell if there is a double-wall exhaust pipe to keep the exhaust super hot into catalyst #2? I wonder if this is what they replace on the TSB at Toyota Service if you complain about exhaust smell coming in the car. If I take the car after my Papa drives it and wail on it getting on the Interstate rt93 I smell stinky sulfur and gunpowder smell in the car. I am guessing if the inner exhaust pipe is melting and closing down and exhaust is leajking oout after the end of the first catalytic converter?

SEVEN · 12-02-2008, 04:31 PM

Ok so if I change my header I have to get a new a/f mixture sensor (it's a megan header)??

TheSilkySmooth · 12-02-2008, 06:31 PM

Quote:

Originally Posted by SEVEN

Ok so if I change my header I have to get a new a/f mixture sensor (it's a megan header)??

NO, you just have to remove the old one CAREFULLY - I would read the Factory toyota maintenance manual ( on here in PDF somewhere) and double check the procedure for R&R-ing the #1 O2 sensor.

eric81 · 12-03-2008, 01:41 AM

Hope the original is not cross threaded. Good luck!

eric81 · 12-04-2008, 01:00 PM

The exhaust manifold was getting hot enough to cause me discomfort in the cabin of the car. It was a very hot running engine for a while there. But, it is all better now because I got a new A/F sensor. It is all normal again.

auxmike · 04-21-2012, 09:28 PM

Has anyone swapped out their o2 sensors since this thread started? Anymore crossthreading issues?

12-02-2008, 04:31 PM	#10
SEVEN Drives: 07' HB Black Join Date: Nov 2008 Location: Puerto Rico Posts: 50	Ok so if I change my header I have to get a new a/f mixture sensor (it's a megan header)?? __________________ When life passes you by ... dowshift

04-21-2012, 09:28 PM	#14
auxmike Drives: 2008 HB, A/T, Power W/L/M Join Date: Oct 2008 Location: LI, New Yawk Posts: 2,063	Has anyone swapped out their o2 sensors since this thread started? Anymore crossthreading issues? __________________ Never take eyes off opponent - Bruce Lee

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
NEWS: TOYOTA REVEALS ALL-NEW YARIS SEDAN AT 2006 LOS ANGELES AUTO SHOW	VitzBoy	General Yaris / Vitz Discussion	7	09-20-2023 08:50 AM
2007 Yaris Pricing Info !	YarisBueller	New YARIS Purchase Forum	104	06-24-2009 05:54 PM
1.3 Ltr Yaris Air Filter mods	aucorium	Performance Modifications	9	08-18-2006 09:32 AM
Need LA Yaris liftback Owners for Yaris Commercial	weinsteins	General Yaris / Vitz Discussion	10	05-04-2006 05:42 PM

11-17-2008, 01:55 PM	#1
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	A zero-to-5 V is a wide range Lambda (mixture) sensor which is still technically an oxygen sensor. It just has the ability to read lean and rich conditions which a std O2 can only read (perform a step function form near zero volt output to 1+v output at rich) so the EC unit can run at stoichiometric or "perfect mixture". The Car swith the old system are constantly varying between lean and rich to find the centre. On the 0-5V, Toyota can then run the car a bit lean at light / throttle light load. This is like what a dyno tune shop uses for a sensor. They Used to be big bucks and I though aonly used on the Prius - but the tech must have trickeled down the inexpensive Yaris. Now the mystery of the awesome gas mileage (with my dad driving at least) is solved! Yeah, dad gets 40 and sis gets 35! sonja's bro (Our family, we got to get separate logins! but we love the Yaris World!) Last edited by TheSilkySmooth; 11-17-2008 at 01:56 PM. Reason: tell U who I am

11-17-2008, 02:05 PM	#2
kou View User's Garage Drives: 08 lb Join Date: Aug 2007 Location: nj Posts: 935	any time you have to change an o2 sensor i have found you should heat the area of the pipe/manifold around it,this usualy gets even the rusted ones out.

11-17-2008, 07:26 PM	#3
Return of the Yarii Drives: 2007 Sedan S Join Date: Oct 2008 Location: Naperville, IL Posts: 53	I have an 07 Sedan and mine was crossthreaded, found out when I did DC header install, bought a new one from Ken @ Sparks. Its listed in the classifieds along w/the header. It is indeed an Air/Fuel Sensor, the O2 sensor is downstream pending sale of A/F Sensor to member on the board

11-18-2008, 09:35 AM	#5
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	And NOW, to put me in the running for the big dick head award: The auto repair industry recognises MIL* for what we've been calling a CEL. I know this is "Down wid teh MANg Age" but very soon if not now NO ONE will know what anybody is talking about if we all make up our own terms for stuff and do not use the proper term. *MIL = malfunction indicator lamp White Cholera Woiker

11-18-2008, 12:01 PM	#6
eric81 View User's Garage Drives: Toyota Salesman Join Date: Nov 2008 Location: Clarksville, IN Posts: 297	The Silky Smooth is far too smart to be from earth. We have aliens. Anyone got any Raid? Anyone? And what exactly does that mean anyways? The Silky Smooth... what is so silky smooth? I don't understand? Still, crossthreaded A?F sensors suck, and they keep us from being able to use our aftermarket parts without replacing a bunch of other stuff. I also recommend checking the little silver bolts on the top of your engine that hold the spark plugs in place (they are black, have one bolt in them, and there are four of them across the top of the engine) to see if their bolts are as bad as mine were. They used a cheap bolt on mine and I snapped it in half trying to put it back in place. I took a different one out to measure it at the hardware store, and it was all stretched and warped too. So I replaced them all, and they were all bad. Toyota sure did save those pennies when it came to our cars.

11-19-2008, 01:53 PM	#8
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	I am the silky smooth brother , not the silky smooth. I wouldn't think the factory would cross thread the sensor - maybe it was fused to the bung on purpose? Does any tech on here know if the header sensor comes together as one part#? This is all basic stuff if you are a tech or read tuner mags and forums a lot. Gotta get out there and Ed-U-Kate yosef

11-19-2008, 01:58 PM	#9
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	Thread Hijack Any one pulling off the headers - can you tell if there is a double-wall exhaust pipe to keep the exhaust super hot into catalyst #2? I wonder if this is what they replace on the TSB at Toyota Service if you complain about exhaust smell coming in the car. If I take the car after my Papa drives it and wail on it getting on the Interstate rt93 I smell stinky sulfur and gunpowder smell in the car. I am guessing if the inner exhaust pipe is melting and closing down and exhaust is leajking oout after the end of the first catalytic converter?

12-03-2008, 01:41 AM	#12
eric81 View User's Garage Drives: Toyota Salesman Join Date: Nov 2008 Location: Clarksville, IN Posts: 297	Hope the original is not cross threaded. Good luck!

12-04-2008, 01:00 PM	#13
eric81 View User's Garage Drives: Toyota Salesman Join Date: Nov 2008 Location: Clarksville, IN Posts: 297	The exhaust manifold was getting hot enough to cause me discomfort in the cabin of the car. It was a very hot running engine for a while there. But, it is all better now because I got a new A/F sensor. It is all normal again.