What is a Wideband Sensor and Which iWire Plug and Play Wideband Kit Should I Get?

What is a Wideband Sensor and Which iWire Plug and Play Wideband Kit Should I Get?

Jul 11, '21

In this blog post we go over what a Wideband sensor is and why we recommend it for your Subaru.


What is a Wideband Sensor and Why Do I Need It?

A wideband sensor reads the air/fuel mixture of exhaust gases to determine how the engine is running. When modifying the engine (IE new exhaust or big turbo), the tuner needs to know the true air/fuel mixture to recalibrate the ECU properly for the new setup. Although the factory front O2 sensor does this and is a considered a "wideband" O2 sensor, it's not as precise as a true wideband O2 sensor.


iWire recommends installing a full time wideband O2 sensor when any engine upgrades are made. When tuning on a dyno (or at least with the car in person) a tuner could mount a temporary wideband O2 sensor and connect it to their laptop via a USB or serial connection. From there, the tuner can compile the data from the O2 with the rest of the ECU using their advanced tuning software. This can be a pain for the tuner to do and doesn't help if the driver needs to send a data log for a future update or diagnostic report to the tuner.


What makes the iWire Wideband Kit Different?


There are two reasons our wideband kits are different than the competitors.

1. The customer just plugs it in for install. No soldering, crimping, or wiring diagrams here. Easier install means more time behind the wheel.

2. The iWire wideband is prewired for data logging. No extra set up or wiring is needed. It automatically is data logging the air to fuel ratio for you once you get an updated ECU map from your tuner so the ECU can understand the change. 

NOTE: With COBB's Greenspeed Update there is no current option to datalog with the AP at this time. This feature would still work if you utilize other tuning platforms. Please reach out if you have any questions.


Which Wideband Should I Get?

iWire currently offers two versions of the AEM Wideband. See pictures below.


iWire Wideband Without Gauge

 iWire Recommendation:

Our recommendation is based on what type of ECU you have – 16 bit vs 32 bit. It also depends if you happen to like gauges or not. If a clean interior is desired we suggest our wideband without gauge. If there is already a gauge pod in the car then the wideband with gauge is a great option.


16 Bit ECU

- 2002-2005 US WRX

- 2001-2006 JDM WRX

- 2001-2006 JDM STi

For these cars we recommend the iWire Wideband with Gauge. The Cobb AP does not have required custom features to get the display on the AP to show the data as the actual air/fuel ratio (IE 14.7). Instead it just shows the raw 0-5v value which probably won't be as ideal to display so the physical gauge to keep an eye on this information is a nice feature while the ECU is still logging the data for the tuner.

 32 Bit ECU

- 2006-2014 WRX

- 2004+ STi

- 2004-2013 Forester XT

- 2005+ Legacy GT/Outback XT

These cars could utilize either wideband kit but we generally recommend the iWire Wideband without Gauge. It’s an easier install since you don’t have to run any wires through the firewall and the Cobb AP can be utilized as an actual air/fuel ratio gauge for the driver to monitor.

Check out our install videos below:

 iWire Wideband without Gauge Install Video

iWire Wideband with Gauge