Best location to install o2 sensor for AEM Wideband guage?

[yipiokayyay]

Hi I bought an AEM wideband guage and need to find a muffler shop to help me install the o2 Sensor. But I don't know where to ask them to weld it.

Everything in exhaust system is OEM except for aftermarket exhaust. I am thinking about just doing it after the catalytic converter but before the muffler since I don't want to mess up any OEM parts.

Do folks here have a recommendation?

 

[Honcho]

Hi I bought an AEM wideband guage and need to find a muffler shop to help me install the o2 Sensor. But I don't know where to ask them to weld it.

Everything in exhaust system is OEM except for aftermarket exhaust. I am thinking about just doing it after the catalytic converter but before the muffler since I don't want to mess up any OEM parts.

Do folks here have a recommendation

You must place the wideband sensor before the catalytic converter or your AFR readings will be completely wrong. If you have an OEM exhaust manifold, you will have to have a fabricator weld a bung into the tube that connects to the cat. The sensor must be top-mounted between the 9:00 and 3:00 position on the pipe. I installed mine on the front bank pipe, but I have headers, so I put it on the header adapter.

 

[Old Guy]

I don't know whether the AEM wideband controllers will do this; but, a lot of wideband controllers will provide the typical 0-5V linear output signal and a second highly non linear 0-1V output signal which emulates a narrow band sensor. The theory is that you can install your wideband in the existing pre cat sensor location and then use the narrowband output to connect to the ECU. Saves you welding in a new bung. That is the theory; but, the results can be hit and miss depending on the wideband controller and the ECU. Since the ECU checks the status of the O2 sensor heater you will need to fake the heater circuit if you want to avoid generating a DTC for O2 heater failure.

You are aware that since the engine is a V 6, you technically need two wideband sensors (front and rear). The OEM ECU runs separate exhaust corrections on the front and rear cylinder banks so the AFR you read on the front bank may not be the same as the AFR you read on the rear bank.

 

[Optical]

I don't think the AEM WB has the narrowband output simulation. The Innovate WB might be a better option to make use of this.

Agree with what's been said above. Must be upstream of the CAT. Also nothing kills the sensor quicker than water (condensation) being splashed onto it when hot. For this reason, putting it on the top side of the pipe, and preferably uphill from any condensation collection points are the best rule of thumb.

 

[Honcho]

I don't think the AEM WB has the narrowband output simulation. The Innovate WB might be a better option to make use of this.

Agree with what's been said above. Must be upstream of the CAT. Also nothing kills the sensor quicker than water (condensation) being splashed onto it when hot. For this reason, putting it on the top side of the pipe, and preferably uphill from any condensation collection points are the best rule of thumb.

Agree. I use the Innovate LC-2 and it does have a narrowband signal wire. I installed it in its own port though. Ideally, once the car is fully tuned, I'd like to remove the Demon/Wideband and burn a chip.

 

[Old Guy]

The other contributor to long sensor life is not starting up the O2 sensor until after the engine has started. Powering the wide band controller up off of the same supply as the fuel pump is an easy way to do that. The 14Point7 Spartan 3 wideband has an interesting feature that powers up the senor heater once the exhaust temperature hits a minimum threshold. That would be nice feature if it works reliably. The Spartan 3 also has a separate simulated narrow band output.