derrick92130

I got my new wide band O2 sensor (got the prebuilt unit from TechEdge) and had a bung welded onto my exhaust system on the engine side of the front Cat (2000 4Runner, California model). I works beautiful for about 5 minutes, then starts sending garbage to my reading device.

I have been told that I may have it too close to the engine as the wide band sensors can not operate in the extreme temps that a narrow band sensor can?

If I move it any further back, it will have to go between the two Cats and am concerned about accuracy. I read about an O2 bybass tube that skips the front Cat for the O2 sensor but am concerned about remaining emission compliant.

Is anyone running a wide band sensor on a CA model with the dual cats that can confirm their placement of the sensor?

Thanks!

Gadget

It has to be in front of both cats.

I have the same unit and I have had no issues at all. I know one thing to be concerned about is mounting it on the bottom of the pipe in such a way that the water that builds up in the exhaust will not run into the sensor. If it does you will have a problem.

You might want to email the folks in OZ and ask them what is up.

Gadget

www.GadgetOnline.com

derrick92130

Thanks Gadget. I am running their new 2.0 unit with the Bosch 6 066 sensor. I pulled the front cat out and mounted it on the top, right next to the factory front O2 sensor. I put it there so I wouldn't have the water issue you described in your email.

I'll email Peter and see if he has an idea what is going on.

Thanks again

derrick92130

Quick Update.

I exchanged emails with Peter (TechEdge) today. He states that all units previous to the V2.0 devices did not have closed loop control of the O2 heater and cannot report if the exhaust temperature is deemed to be "too hot".

I've got one quick test of the unit to ensure there are no issues in the monitoring unit, but is pretty certain that it is this "heater PID lock" capability.

Sounds like I may be re-routing my exhaust (bypass) to accomodate the O2 sensor...

Gadget

OK, so what does all that mean?

Gadget

www.GadgetOnline.com

derrick92130

This wideband sensor (Bosch 6 066) is a five wire sensor. My understanding is that it also communicates its temperature (or at least the over-temp condition) to the controller if it reaches 850 degrees C (1562 degrees F) or greater. The controller then shuts off the power to the heater and and as a result cannot maintain the internal sense cell impedance.

Unfortunately, I am not running an EGT at this point, but am a little surprised that I am running this hot as the A/F ratio is sitting almost perfectly at 14.7 at idle and it will eventually overheat the O2 sensor just idling.

cstary

why would it overheat the sensor at idle? your EGT's are around 400-600 or so at idle, especially way back by the cat. they only reach peak (1450+) at wide open throttle, and then only transiently.

those WB sensors are supposed to be accurate across a range of temps . . . sounds like there's more of a major problem with the unit and you should probably have it replaced.

by the way, what was the final cost out the door, sensor, shipping and everything?

creed

derrick92130

Great. Sounds like I am back to the guys in OZ.

The whole unit (Bosch 6 066 sensor, cable, LED display and base unit) ran me $457.05 shipped to my door.

cstary

hope you get it straightened out. i was planning on buying that setup . . . please keep us posted.

creed

derrick92130

Creed,

Once I get this going, I would be more than happy to share the WBO2 unit with you (easy since you are local here in San Diego).

I'm going to pull the O2 sensor and verify that everything is ok on the bung that was welded on. I want to be sure there are no obstructions, welded centered on the hole, etc.

Next, I figured I would put it further down the exhaust path (I recognize it will not provide an accurate reading) just for the purpose of validating that it still has the problem regardless of the "heat".

If the problem persists, then I can work with the folks in OZ to replace/repair if necessary.

Other ideas are welcomed!

PM me and let me know where you live in SD!

derrick92130

Just a quick update. Looks like Creed and Gadget were right (as usual), and the sensor is not overtemp. I am working with TechEdge to diagnose the problem with the sensor/cable/unit. I'll post the results when I have them.

derrick92130

ISSUE RESOLVED.

I realized that I never posted the final results on this thread. Peter at TechEdge researched this issue with the new V2.0 of the WBO2 sensor and identified an "increased sensitivity" with that unit to heat (with the new sensors). A quick update to the firmware and I am back in business, with the WBO2 sensor in the original location on the engine side of the front CAT.

Works beautiful and I am back to tuning...

Great unit, really works well.

-Derrick