Here's the situation. b16a in a 1989 EF Hatch. obd0, sensors have one wire coming out of them.

I'm permanently installing an AEM wideband. I have a narrowband in the car. It was installed by the previous owner. Look at this wiring garbage under the car. I believe the one sensor including the 3 splices you can see, has 3 more on it's way up the harness, and the other one in the header is just as bad, and I believe is paralleled off and running my narrowband. Loose wires, bad splices and crappy fitting connectors are EVERYWHERE...*ugh*.

The fittings on the 02 mount on the resonator appear to be leaking and about rusted through (on the other side, doesn't show in pic).

I just want to start over, weld on new bungs with better fitment and run new wiring, and include the wideband.

the questions,

a) Do I need both of the existing 02 sensors? (shown in the pic)

b) If I can remove one, which one?

c) Where best to mount the wideband?




Many thanks.

-Vector


Modified by vectorsolid at 2:13 AM 6/18/2008

 

I am not 100% sure but I doubt you could remove one of the sensors. Although, to my knoledge obd0 and obd1 cars only need 1 o2 sensor. The 2 sensors are supposed to work with each other to check the efficency of the motor. Primary o2 is to get a gross AFR reading, and the secondary is supposed to read what the gas is like after the catalytic.

You SHOULD be abel to remove 1 of the o2 sensors, and if you can, it would be the rear one.

As for where to install the wide band, I would put it just infront of the catalytic to get the best readings. However, a better bet would be to contact the manufacture of the sensor and ask them where its best to place it, as they would know where its designed to work best.

ETA: The B16 swap in my EF has the same wiring set up (hacked) but the o2 sensors are placed right next to each other on opposite sides of the pipe

 

If you are running a PR3 or PWO ECU then it reads both O2 sensors as primary. They are supposed to be 1 for cyl 1/ 2 and 1 for cyl 3/4.

By installing a wideband O2 you will not change anything and will throw a check engine light.

If you are converting it to OBD1 then you want the O2 sensor either in the manifold collector where all 4 cyl's meet or just before the cat. converter. OBD1 can support the wideband if you have the correct engine management system.

 

I was having some issues of my car "jerking" around, I disconnected the only O2 sensor wired up (OBD1/B16A2) and it fixed it, so now I run w/o an O2 sensor. Is that harming anything? If I run both O2 sensors correctly will that help me gain any additional power? WTF do we need an O2 sensor for? I know I talked to the guys @ phearable.net and they said they bypass O2 sensor on many of there OBD1 ECU's.

 

The OBD1 is different than the 1st gen B16 using a PR3/PWO ECU.

The O2 sensor measures how much Oxygen(O2) is present in the exhaust after the burn in the combustion chamber. The ECU uses this information to adjust the Air/Fuel ratio. The O2 sensor will measure high/low/high/low many times per second due to the ECU making the engine run rich/lean/rich/lean as it attempts to adjust to the ratio.
On the PR3/PWO ECU's it adjusts cyl 1/2 and 3/4 seperatly instead of all 4 at once.

When the ECU does not have a reading from the O2 sensor the ECU will be in "open loop" which it then runs on a predetermined program(usually rich) until the O2 sensor is hot and sending signal to the ECU. Once the ECU sees and interprets the signal from the O2 sensor the ECU is now in "closed loop".

On OBD2 vehicles there is an O2 sensor before and after the cat. converter. The pre cat O2 sensor measures the O2 and the ECU will adjust A/F ratio based on this reading while the post cat O2 measures and the ECU uses this info to determine if the cat. converter is being efficient or not.

 

If you are running an aftermarket programmable engine management system then the O2 sensor(ususlly wideband) is used to determine A/F ratio while programming.
Once it is programmed then there is no need for an O2 sensor as the Engine management system is running on a predetermined program.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgallagher &raquo;</TD></TR><TR><TD CLASS="quote">If you are running an aftermarket programmable engine management system then the O2 sensor(ususlly wideband) is used to determine A/F ratio while programming.
Once it is programmed then there is no need for an O2 sensor as the Engine management system is running on a predetermined program.</TD></TR></TABLE>

Is it possible I could parallel the wires to just one of the 02 sensors? Rather than running both, and then run the wideband in the other hole?

This isn't a daily driver, it's a car I'm piddling with, so I want to permanently mount the wideband, just to watch what's going on.

 

No you cannot run the wires together.

Run a manifold like the OEM style with the 2 O2 sensor ports. Then if you want put a bung after the collector and run your wideband there.

 

Is there a single 02 sensor that could be wired in place of the two that would work?

 

NO, not properly.

 

So, the best case senario, is for me to have two o2 sensors, AND the wideband, all poking around in there. No way around it?

Just have to go in and re-wire the junk, without removing any of it. Sound about right?

 

So what you are saying is that the O2 sensor is used to maintain fuel efficiency by adjusting the A/F based on it's readings. So running without the O2 just makes it run the pre programmed all the time which is more rich, which in turn is making my car not as fuel effiecent?
And if I were to run my O2 correctly then I would need (2) O2 Sensors? (I believe I have the PR3) both before the cat?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vectorsolid &raquo;</TD></TR><TR><TD CLASS="quote">
So, the best case senario, is for me to have two o2 sensors, AND the wideband, all poking around in there. No way around it?

Just have to go in and re-wire the junk, without removing any of it. Sound about right? </TD></TR></TABLE>
no, I have a solution to your problem. Don't buy the AEM wideband.

Instead, buy a Innovate LC-1. Then you have 2 programmable analog outputs from 1 sensor. This solves your problem because you can then choose an existing o2 sensor to leave in your car. Then, you run the LC-1 as your other sensor, where one output is your "narrowband" to the ecu, and the other output on the LC-1 is your wideband to a guage or box or your laptop or whatever you were planning on using to monitor the A/F ratio.

The best part is: its still much cheaper than the AEM part, and you get to remove one of the crappy one wires and still make everything work as stock, no ecu chipping, etc, etc.


Modified by sanimalp at 5:21 PM 6/18/2008

 

do what he ^ said if you dont have a chipped ecu. in the future if you run something like hondata/neptune/etc...(obd-1) you can run just your wideband sensor. then you can choose if you want it to run open loop all the time(car running off your settings) or you can run closed loop if you choose to as well.


doing it the way sanimalp is best if you are stuck with the obd-0 pr3 ecu.

 

If you choose to run it like sanimalp suggests. Do it with the O2 in front of the cat. You should not have an O2 sensor after the cat. converter. If you do the readings will not be correct because the catalyst has come into effect.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgallagher &raquo;</TD></TR><TR><TD CLASS="quote">If you choose to run it like sanimalp suggests. Do it with the O2 in front of the cat. You should not have an O2 sensor after the cat. converter. If you do the readings will not be correct because the catalyst has come into effect.
</TD></TR></TABLE>

I'm no Cali BAR ref, but that doesnt look much like a cat to me

either way, the wideband should go as close to the engine as possible, as everyone has said.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sanimalp &raquo;</TD></TR><TR><TD CLASS="quote">
no, I have a solution to your problem. Don't buy the AEM wideband. </TD></TR></TABLE>

To late on that, already picked it up.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sanimalp &raquo;</TD></TR><TR><TD CLASS="quote">
Instead, buy a Innovate LC-1. Then you have 2 programmable analog outputs from 1 sensor. This solves your problem because you can then choose an existing o2 sensor to leave in your car. Then, you run the LC-1 as your other sensor, where one output is your "narrowband" to the ecu, and the other output on the LC-1 is your wideband to a guage or box or your laptop or whatever you were planning on using to monitor the A/F ratio.

The best part is: its still much cheaper than the AEM part, and you get to remove one of the crappy one wires and still make everything work as stock, no ecu chipping, etc, etc.</TD></TR></TABLE>

Sounds like a decent idea though. Although still $400 with a gauge. I just like the gauge in the car, and I'm fiddling with stuff, I'd like to see what it's doing, roughly.


Modified by vectorsolid at 1:09 AM 6/19/2008