Rear O2 sensor removal for wideband.

[szewczyd]

I recently ran into an electrical issue when trying to install my wideband into my second O2 sensor location in my downpipe. We cut the 4 wires that go to the O2 sensor the two black ones, a white, and a blue. We taped the ends up and tucked them back in and then wired in the wideband. We then went to start the car and it now barely runs and I mean barely took 2 hrs to get it to start and runs super rich, and I have to hold the gas pedal to keep it semi running. It sounds as if the engine is missing badly or not firing in the right order.

 

[szewczyd]

I was thinking maybe we fried or shorted something out or that you cannot just cut the O2 sensor and leave the wires like that?

 

[CanadianTSi]

The rear o2 only lets the car know if the cat is working.

I cut the wires to my rear o2 3 years ago and just left them, the only problem this causes is a CEL...nothing else.

 

[szewczyd]

Thanks I just wanted to rule that out, that the O2 sensor has nothing to do with the running of the vehicle.

 

[jepherz]

You can put some resistors/caps inline with the wires to get the CEL to go away. Do you have a cat still? If so, I'm not sure why you're planning on running the wideband in that position...

 

[Lordpaxin]

what is the point of wide band tuning a car running stock exhaust.

 

[FORMONTOYA]

If you cut all 4 wires, or actually the +/- at the same time, then yes, you could have shorted something. However, if you cut the 4 wires individually and then taped them up, you should be ok.

I would at least check to make sure that the tape job held and didn't just fall off when you were tucking everything out of the way just to be sure.

As stated, all he rear O2 does is check for cat operation, however, the wires do go back into the ECU and any shorts heading there is not a good thing.

 

[FORMONTOYA]

what is the point of wide band tuning a car running stock exhaust.

What about my 3" turbo back with a 3" high flow cat. I am not going to put the WB O2 sensor in the stock rear O2 spot (after cat). I will put it in the DP, but I will still have the cat in place.

 

[szewczyd]

I have a cat on but it is completely empty and knocked out so no I really don't have one. I am going to try my buddies ECU in my car tomorrow after I get my car trailer and trailer it home...dang AWD!

 

[Lordpaxin]

What about my 3" turbo back with a 3" high flow cat. I am not going to put the WB O2 sensor in the stock rear O2 spot (after cat). I will put it in the DP, but I will still have the cat in place.

whats that got to do wtih anything

 

[FORMONTOYA]

whats that got to do wtih anything

It has to do with the location of the WB sensor location. The accuracy of the reading will be off/delayed if put after the cat, which is what I thought you were insinuating about the stock exhaust comment. If running a cat, most WB sensor manufacturers suggest putting the sensor before the cat. Hence my comment of putting it in the DP.

A WB sensor would give more accurate information about how the car is running over the OEM NB O2 sensor even with a OEM exhaust system which is what tuning is all about, accurate information to make judgments off of.

If I misunderstood your comment, I apologize.

 

[Lordpaxin]

i meant that what is the point, if you are still running stock exhaust, why are you modifying fuel anyway?

I like to keep the sensors just before the flex. cause the flex is usualy the first point that starts to leak on me,

 

[szewczyd]

I know you guys said that the o2 sensor has no affect on the driveablity but look at this, and this seems to be exactly what my car is kinda doing.
http://www.bennettauto.com/oxygen_sensors.html

 

[DGajre777]

I know you guys said that the o2 sensor has no affect on the driveablity but look at this, and this seems to be exactly what my car is kinda doing.
http://www.bennettauto.com/oxygen_sensors.html

The front o2 sensor affects driveability.
The rear o2 sensor does NOT affect driveability, it is there just to check if the cat is working.

If the cat is removed, the rear o2 sensor triggers the CEL. There are 3 ways around the CEL, 1) to do the rear o2 mod 2) to install an o2 simulator and 3) to leave the o2 sensor out of the exhaust open to atmosphere.

 

[Gamble97]

I have had a apex n1 turbo back on my car w/ no cat for about 4 months and have no check engine light on.
Also, I did my wideband yesterday too. I just unplugged the 2nd o2 and ran the white wire from the 02 to the wideband. I left the other wire plugged into the connector and the connector just hanging

 

[szewczyd]

Well I am going to be looking more in depth today and try and figure out what the heck is up!

 

[97ebaygst]

i know its been a few years since the last post started but has szewczyd figured out what the problem was? i'm in a similar situation and would like the input.