I am currently switching over to a wideband O2 sensor/gauge, and the car idles fine for about 30 seconds, then the car leans out and dies. Whenever I use the narrowband stock sensor this doesn't happen, it actually run just fine. Right now I'm prepping the car to custom tune it since it's a HSR/383/big cam.

Has anyone dealt with this before? Does the wideband sensor function different that could cause this? Is it b/c it's not tuned?

 

What kind of signal are you sending to the ecm from that wideband sensor? If its not altered then yes, its not going to work right.

 

The wideband goes to an AFR gauge correct? It doesn't send data to the ECM. Your ECM couldn't use the data from the wideband. Most wideband O2 controllers have a narrow band O2 simulator output but it's useless for actually replacing the narrow bands signal to the ECM. If you are using this feature, that would explain the engine running lean. Otherwise, if you are removing the narrow band O2 and leaving the ECM's O2 sensor connector hanging while you run the wideband, your modified engine is probably running lean without Block Learn(long term fuel trim) correction. Getting your fuel management properly tuned will correct this.

 

Yes, it goes to a gauge. I connected the WB sensor to the existing signal wire from ECM (purple wire) and used the ECM/block ground for my sensor (tan wire). I didn't leave the existing wire hanging, I'm actually using it for my signal wire.

Is this the correct way to wire it?

 

Oh no. The wideband O2 produces an entirely different signal. The narrow band ECM doesn't know what to do with it. Most wideband O2 sensors are used with an AFR gauge that allows us to see actual AFR in real time. Some newer and aftermarket Fuel Injection controllers use wideband O2 sensors. Using the wideband input, these systems can actually self calibrate.

 

So, should I keep the existing sensor and add the new WB sensor in the other header tube? Or will the new custom tune allow the ECM to recognize the WB signal?

 

Anyone??

 

Yea you need to use a factory style sensor to communicate to the ECM, the wideband should have its own bung, I'd imagine somewhere near the Y in the exhaust for an accurate reading.

 

That's what I thought......I'll just mount it in the right bank header tube.