Running without o2 sensor

[SoguRacing]

Ok guys, i just bought a megan turbo elbow and its for a fat o2 sensor and my redtop has a skinny o2 sensor. Question...What to do...Do I run without an o2 sensor? The car is obd 1 so the o2 sensor doesn't do much though it will improve gas mileage at cruising speeds.
Or..do i weld the skinny o2sensor to the fat bung and hope that it works.

I know there's other options but dont really want to go out and buy a fatty o2 sensor or another elbow to suit my needs. Any help is appreciated. thanks:aw:

[fliprayzin240sx]

There should be an adapter for the skinny o2

[dtc 360RT]

I think theres adapters availiable....also I know the stock exhaust manifold on an sohc has and adapter. I figured that out when I put headers on my sohc, I unscrewed the o2 and it was obviously to skinny for the hole on my headers then I realized I could unscrew the other part on my exhaust manifold. I have an extra one you can have, wortha try?

[SoguRacing]

I didn't know about that. I'll search around. oh and thanks for the rep bump on the DIY thread.

[SoguRacing]

So you have an adapter for it? something that screws into the fatty and threads it down to the skinny? sounds good. where you at? pm me.

[KiLLeR2001]

You can order the adapter piece from Nissan if you have to. I believe its around $11.

Part #: 20607-V5000

[GSXRJJordan]

Yeah, all the new Megan elbows come with an adapter. I drilled/tapped my "plug" to fit the skinny one once, and then on my next one just got a blacktop o2 sensor that fit the hole, and then replaced that elbow and the new one had the adapter :)

Don't run without an o2 sensor if you can help it.

[SoguRacing]

i can't find a site that sells it. I have a nissan dealer right around the corner, i'll just hit them up. thanks guys! +1

[Sileighty_85]

this ones more expensive but if ya can't find it at the dealer her ya go http://enjukuracing.com/spec-sensor-adapter-nissan-sr20det-p-6408.html?cPath=24_57

[g6civcx]

What to do

Run a Z32 O2 sensor. Problem solved.

Cliff's notes of the earlier o2 threads:

Some say skinny and fatty are different and not interchangeable.

I say if you can show the data stream for a skinny vs. a fatty on the same engine and recording data at the same time, then maybe you can make a case that they're different. But even then, you have to show that the ECU is actually processing the two signals differently somehow.

So far no one cared enough to do this so run whatever you want.

[clark]

^--spot on.

depending how crusty and old your skinny o2 sensor is, just pick up a new fat type o2 sensor from a z32. same plug and everything. the exact details are in the SR20DET FAQs.

just look at it this way, do you REALLY wanna waste your time buying an adapter to adapt the skinny type that isn't even available here?

it's like buying a big as TV antenna and putting it on your roof, which is a waste because they're turnign off analog air broadcasts in 2009 anyway lol

[g6civcx]

I don't want to dig it up again, but the big arguments from them was that the skinny and the fatty send a different signal to the ECU, and the ECU gets confused if you mix and match.

My position was that at best the signal is more responsive on one type over the other, but the ECU takes an average of the sensor reading over a period of time, and o2 reading isn't a crucial parameter anyway.

Does anybody want to run some testing?

[Sileighty_85]

Damn beat me too it^^

Its cheaper (here as far a new one goes)

http://www.thenismoshop.com/ikorb.php?func=catalog&category_id=3812&product_id=1607

Fat Vs Skinny One uses a voltage signal and the other uses a resistor
there was a thread on this about a month ago

[g6civcx]

Fat Vs Skinny One uses a voltage signal and the other uses a resistor
there was a thread on this about a month ago

What is the difference between a "voltage signal" and a "resistor"?

[Sileighty_85]

What is the difference between a "voltage signal" and a "resistor"?

you know the thread i'm talking about dont ya?

I think it was this one
http://www.zilvia.net/f/showthread.php?t=158418&highlight=zirconia+ceramic

More Info
http://en.wikipedia.org/wiki/O2_sensor

somthing along the lines of
One sent a signal and the other recived and used a resistior to change the voltage and send it back to the ECU.

[SHIFT_*grind*]

Depending on whether or not you can find it at the dealer, and depending on how much it costs, getting it from Megan might be cheaper. It's not on their website, but you can call them and ask for it directly. $15 shipped. (626)581-0988

A lot cheaper than $20 plus shipping (probably $10) that Enjuku wants. $30? For a bolt? Come the fuck on, guys.

[g6civcx]

you know the thread i'm talking about dont ya?

I think it was this one
http://www.zilvia.net/f/showthread.php?t=158418&highlight=zirconia+ceramic

More Info
http://en.wikipedia.org/wiki/O2_sensor

Yes.

somthing along the lines of
One sent a signal and the other recived and used a resistior to change the voltage and send it back to the ECU.


You are the ECU and I am the O2 sensor. We're connected by a straw (wire) and we can blow spit wads (electrons) at each other.

When I suck spit wads from you, I am a voltage triggered sensor. Electrons flow from negative (you/ECU) to positive electrical potential (me/sensor). I'm sending a signal to you because I'm sucking your spit wads away.

When I blow spit wads at you, I am a current triggered sensor. Electrons flow from negative (me/sensor) to positive electrical potential (you/ECU). I'm sending you resistance because the more resistance I send, the more spit wads will get blown your way.


It has to do with which way the spit wads are going. The ECU has to know whether it wil get blown or sucked :love:


Now, does skinny and fatty each suck or blow?

[KiLLeR2001]

Lets end this. These are your options:

1. Buy $10 adapter piece at the Nissan dealership.
2. Buy an E5 ECU and a Z32 TT fatty o2 sensor.

Hmm decisions, decisions.

[Sileighty_85]

Fatty - Blows

The zirconium dioxide (http://en.wikipedia.org/wiki/Zirconium_dioxide), or zirconia, lambda sensor is based on a solid-state electrochemical fuel cell (http://en.wikipedia.org/wiki/Fuel_cell) called the Nernst cell (http://en.wikipedia.org/w/index.php?title=Nernst_cell&action=edit&redlink=1). Its two electrodes provide an output voltage corresponding to the quantity of oxygen in the exhaust relative to that in the atmosphere.

Skinny - Sucks and Blows

This type does not generate its own voltage, but changes its electrical resistance (http://en.wikipedia.org/wiki/Electrical_resistance) in response to the oxygen concentration. The resistance of the titania is a function of the oxygen partial pressure and the temperature.

[g6civcx]

Lets end this. These are your options:

1. Buy $10 adapter piece at the Nissan dealership.
2. Buy an E5 ECU and a Z32 TT fatty o2 sensor.

Hmm decisions, decisions.

The only possible problem I see with the Megan adaptor is that it doesn't put the tip of the sensor as deep into the exhaust flow as a stock elbow or a fatty. I haven't seen the stock adaptor so I don't know.


We're still trying to figure out which is which, for all those inquiring Zilvian minds.



Fatty - Blows

The zirconium dioxide (http://en.wikipedia.org/wiki/Zirconium_dioxide), or zirconia, lambda sensor is based on a solid-state electrochemical fuel cell (http://en.wikipedia.org/wiki/Fuel_cell) called the Nernst cell (http://en.wikipedia.org/w/index.php?title=Nernst_cell&action=edit&redlink=1). Its two electrodes provide an output voltage corresponding to the quantity of oxygen in the exhaust relative to that in the atmosphere.

I only see one wire output for the sensor signal. Where does the other electrode go? Also, when you blow electrons at the ECU, this current triggered, not voltage triggered. Remember that electrons go from (-) to (+).

Skinny - Sucks and Blows

This type does not generate its own voltage, but changes its electrical resistance (http://en.wikipedia.org/wiki/Electrical_resistance) in response to the oxygen concentration. The resistance of the titania is a function of the oxygen partial pressure and the temperature.

I don't see how a single sensor can both suck and blow. Can you explain?


How do you know if the skinny is not a Nernst cell?

[flip3d]

So they arent interchangeable? I'm using the fatty on my redtop. When I first give it some throttle, the A/F goes to 20 then takes a couple seconds to get back down to 14.7

Should I be using the skinny one? I have the 62 ECU.

[Sileighty_85]

I only see one wire output for the sensor signal. Where does the other electrode go? Also, when you blow electrons at the ECU, this current triggered, not voltage triggered. Remember that electrons go from (-) to (+).

two electrodes provide an output voltage corresponding to the quantity of oxygen in the exhaust relative to that in the atmosphere.

The tip reads the exhaust and the outer body reads the outside atomshere. The two electrodes are the 02 body and the tip.

yes Im very aware that electrons go from (-) to (+) such as lightining travles from the ground to the sky.


I don't see how a single sensor can both suck and blow. Can you explain?

Ok this sucking and blowing thing sounds gay, why dont we just say Send and Receive
control unit feeds the sensor with a small electrical current and measures the resulting voltage across the sensor



How do you know if the skinny is not a Nernst cell?
the skinny is a Titania sensor which has a ceramic element

Zirconia sensor is based off of the Nernst Cell.

So thats how i know the skinny is not a Nernst Cell

[KiLLeR2001]

So they arent interchangeable? I'm using the fatty on my redtop. When I first give it some throttle, the A/F goes to 20 then takes a couple seconds to get back down to 14.7

Should I be using the skinny one? I have the 62 ECU.

Get the skinny o2. ('87 Turbo 300zx). And the adapter piece., see if the A/F no longer jumps to 20 and remains around 14.7.

[Sileighty_85]

Get the skinny o2. ('87 Turbo 300zx). And the adapter piece., see if the A/F no longer jumps to 20 and remains around 14.7.

its cheaper from here $63
http://www.thenismoshop.com/ikorb.php?func=catalog&category_id=3812&product_id=1607

Autozone wants like 90-100 bucks

[SoguRacing]

Wow, didn't think this thread would go this far.. i'm off to get the adapter piece. seeing that i'll be at WOT most of the time or at a stop, the sensor probably won't be as crucial to my performance as some might think. 11 bucks is a bargain. :)

[GSXRJJordan]

I also use a fatty sensor on a redtop, with no 'known' problems... but I'd love to see if your A/Fs change, Killer2001.

[KiLLeR2001]

I also use a fatty sensor on a redtop, with no 'known' problems... but I'd love to see if your A/Fs change, Killer2001.

You mean "flip3d". He has the fatty sensor with the redtop.. I've got the skinny o2 sensor for my redtop. No problems here. :)

[flip3d]

I swapped in the skinny. I get wayy better milage but my turbo timer wont display the A/F. The signal wire is ecu pin 19, correct?

[will_drift_4_food]

I swapped in the skinny. I get wayy better milage but my turbo timer wont display the A/F.

This is to be expected. With the Zirconia sensor, which is more-or-less universal, each possible voltage in the range of 0-1V correlates to a specific AFR (coarse), so the turbo timer is able to translate the voltage signal to an AFR. Since the Titania sensor is so rarely used, I doubt they saw much point in using valuable IC space to provide that option. The signal wire is ecu pin 19, correct? Yes, that is correct, except in the case of certain Type-X (J4) ECUs.

240Atlanta Thread HERE (http://forums.nicoclub.com/preparing-to-put-in-new-wire-harness-i-have-a-few-questions-w-pics-t297604.html)

[benarovi]

get more cool backfires and shittier gas mileage
i ran no sensor for aobut a year it was fine, when i put it back in i didnt see a difference at all except for gas and backfiring

[Boost_Fiend]

I've been running w/o a sensor for a while to. Im running emanage though. Car runs fine. Whenever I have my sensor plugged in my car runs really rich, afr's stay at 11-12. I think it may have gone bad.

[will_drift_4_food]

I know that this is an old(-ish) thread, but NOWHERE have I found a definitive list of ECUs and what o2 sensor they are running. Maybe folks can contribute what they know to be the ABSOLUTE correct ECU+o2 sensor combinations. I purchased my blacktop S13 motor from a reputable dealer, straight from Japan. It came with a chipped E5 ECU, which is now stock due to presumably being tuned for a Z32 MAF. After I unloaded the motor at home, I noticed that it had a shimmed actuator, and the turbo coolant lines had been removed. Later yet I found that it had a skinny (Titania) sensor screwed into the elbow with no wires coming out of it, and one t25 flange stud was broken in the manifold. I didn't think much of any of these things, and others have reported similar experiences, so I just added them to my to-do list. I do believe that since someone has modified the motor in the past, it is not unlikely that they didn't run an o2 sensor at all, and just put the S13 redtop elbow on as a replacement. The only motors that the importer was getting at that time were S13 blacktops, so I never really questioned whether the ECU I had was correct for my motor.

I bought the fat sensor and plugged it in. I run rich off-throttle, but it I can tell that the ECU is making corrections by the UEGO going from 11.2-13.7, but sometimes lower than 10.0 (which means I have no idea the real AFR, thanks AEM. I kid). Honestly, I believe that to be a combination of IACV adjustment, incorrect timing, fouled plugs, and possibly a faulty CTS sensor. All of this hinges on getting my tach working (or Consult wired) so that I can set the timing properly.

My motor is in an AE86 chassis also, so various other things have changed that may contribute to an overly rich condition.

[fliprayzin240sx]

E5s are blacktop S13 ECUs and runs the fat o2 sensors, is that what you're asking about?

[will_drift_4_food]

E5s are blacktop S13 ECUs and runs the fat o2 sensors, is that what you're asking about?

Yes, that definitely solves the E5 question.

I guess I am asking that a comprehensive SR20det ECU+O2 sensor list be put together. There is much conflicting info out there, and it would be nice for others new to these motors to have a reference, seeing as how they are so misunderstood. I understand that there are ECU threads, and MAF threads, etc., but so far no definitive o2 sensor thread (including which years/models/chassis to use for replacement sensors. Wiring diagrams might also be useful where they differ between sensors, chassis, etc.

[fliprayzin240sx]

Redtops are pretty much the only ones that use the skinny o2 sensors. Everything else after 1993 uses the fat o2 sensors. That means blacktop S13s, all notchtops (S14s and S15s).

[Boost_Fiend]

So I have a redtop running with a blacktop ecu. I'm using a skinny o2 sensor. Is this wrong?

[Sileighty_85]

Match O2 with ECU

[will_drift_4_food]

So I have a redtop running with a blacktop ecu. I'm using a skinny o2 sensor. Is this wrong?

In my opinion, yes.

[Boost_Fiend]

Just bought a new sensor from advanced auto for a 95 300zx tt. Changing it tomorrow. Hope it makes a difference

[Boost_Fiend]

Just an update. Put the fat o2 sensor in to match my ecu and the car is running much better with the o2 plugged. It doesn't go pig rich after driving for a couple of minutes. Although for some reason my idle was all screwed up and was about 300rpm high then norm so I had to lower it. And idle is alot richer then it used to be, but im guessing that has something to do with my emanage not being tuned.

[Nicelyphe]

I should def match my ECU with my o2 Sensor >_< Anyone need a Redtop ecu and has an E5 they're willing to trade? If you do, or have an E5 for sale. PM me.

[Sliderintrainin]

the kouki blacktop type x(1997-1998) came with a skinny 02.

[Kingtal0n]

the kouki blacktop type x(1997-1998) came with a skinny 02.

The S13 1998 Type-X Blacktop SR20DET engine came with a J4 ecu and a normal fat O2 sensor.

They stopped using the skinny O2 after the 1992 redtops , iirc.

My $.02:
Buy an AEM wideband gauge, and use the narrowband analog output configured to your desired cruise A/F Ratio. I set mine around 15.2-15.5 for best fuel economy. A redtop ECU automatically jumps to about 1A/F richer during idle after a few seconds, so it will idle around 13.8-14.1 and cruise around 15.2-15.5 when set this way.
This scenario gives you a wideband, which is an amazing tuning tool as well as insurance for the engine in a long term scenario, and will support any modifications you make with assurance the engine is running like it should be... And you get the benefit of a closed loop at whatever air fuel you desire.
This is how mine behaves, your experience may differ!

[Sliderintrainin]

S13 Red Top Vs. S13 Black Top - The differences : SR20DET Forum (rear-drive) - Page 2 (http://forums.nicoclub.com/s13-red-top-vs-s13-black-top-the-differences-t59346-30.html)
2nd page.
The water temp sensor and 02 sensor were changed in the type x blacktop.