AEM X-Series Wideband UEGO AFR Gauge (AEM 30-0300)
Overview
Monitor your engine's air/fuel ratio with precision using the AEM X-Series Wideband UEGO Air/Fuel Ratio Controller Gauge. The compact 52 mm gauge combines a wideband UEGO controller, digital display, and Bosch LSU 4.9 sensor into one versatile package, making it an excellent choice for performance vehicles, tuning applications, data logging, and custom engine builds.
With a bright, easy-to-read digital display and multiple output options, the AEM X-Series gives you the information you need to monitor fueling and make informed tuning decisions.
Key Features
52 mm / 2-1/16" gauge diameter
Integrated wideband UEGO controller
Includes Bosch LSU 4.9 wideband sensor
Includes weld-on O2 sensor bung
Large seven-segment digital display
User-configurable AFR, Lambda, and O2% display
0-5V analog output
RS232 serial output
AEMnet CANbus output
Supports data logging and feedback control
CANbus allows multiple X-Series controllers to be connected
Automatic display dimming
Built-in free-air calibration capability
Supports system voltages up to 16V
Black bezel and black face included
Slim gauge housing for flexible mounting
Product Details
The AEM X-Series Wideband UEGO AFR Gauge & Controller provides real-time monitoring of your engine's air/fuel mixture in a compact, easy-to-install gauge package. The integrated controller works with the included wideband oxygen sensor to measure exhaust oxygen content and calculate air/fuel ratio or Lambda values.
The gauge features a large digital display that can be configured to show AFR, Lambda, or O2 percentage, allowing you to choose the information most useful for your setup. Display settings can also be adjusted between three- and four-digit formats.
For tuning and data acquisition, the AEM X-Series provides 0-5V, RS232, and AEMnet CANbus outputs. These connections allow the gauge to communicate with compatible data-logging and engine-management equipment, making it useful for both street and dedicated performance applications.
The compact housing measures approximately 0.825 inches deep, with an ultra-shallow gauge cup depth of approximately 0.200 inches, giving you more flexibility when choosing a mounting location.
Benefits
Real-time air/fuel ratio monitoring
Helps identify fueling conditions during tuning
Easy-to-read digital display
Multiple display modes for AFR, Lambda, and O2%
Supports professional data logging
Multiple communication outputs
Compact design for flexible installation
Reusable monitoring solution for performance builds
Suitable for EFI, carbureted, and dynamometer applications
Specifications
Brand: AEM Electronics
Part Number: 30-0300
Product Type: Wideband UEGO AFR Gauge & Controller
Gauge Diameter: 52 mm / 2-1/16"
Sensor: Bosch LSU 4.9 Wideband UEGO
Display: Digital Seven-Segment
Display Modes: AFR / Lambda / O2%
Voltage Compatibility: Up to 16V
Analog Output: 0-5V
Serial Output: RS232
Digital Output: AEMnet CANbus
Gauge Depth: 0.825"
Gauge Cup Depth: 0.200"
Face Color: Black
Bezel: Black
Mounting: Universal
Warranty: 12-Month Limited Warranty
AFR Display Range
Gasoline: 8.0:1 to 20.0:1 AFR
Lambda: 0.55 to 2.00
O2: Display configurable
Output ranges vary by fuel type and output method.
Vehicle Fitment
Universal Application
The AEM X-Series Wideband UEGO AFR Gauge is designed for universal installation and can be used across a wide range of performance vehicles and engine configurations.
What's Included
AEM X-Series Wideband UEGO AFR Controller Gauge
Bosch LSU 4.9 wideband sensor
Weld-on O2 sensor bung
Wiring and installation components
Black bezel
Black faceplate
Why Buy From FMS Auto Performance?
At FMS Auto Performance, we specialize in performance parts for enthusiasts who want accurate information and quality components for their builds. We offer genuine products from trusted manufacturers like AEM Electronics, along with knowledgeable customer support to help you choose the right equipment for your vehicle.
Whether you're monitoring a street car, preparing for a dyno session, or building a dedicated performance vehicle, we're here to help you get the right parts for the job.
Shipping Information
Fast Shipping Available
Secure Packaging
Tracking Included
Genuine AEM Electronics Product
Expert Customer Support
California Emissions Notice
✅ Emissions Friendly / Universal
This product is listed as emissions code 5, meaning it does not affect vehicle emissions and is not covered by emissions regulations. It is listed for use on emissions-controlled vehicles, non-emissions-controlled vehicles, and racing applications.
Disclaimer
Professional installation is recommended. Always follow the manufacturer's installation instructions and verify that the sensor, wiring, and gauge are properly installed before operating the vehicle. Air/fuel ratio readings should be interpreted appropriately for the fuel being used.