AEM X-Series Gauge (Wideband UEGO Air/Fuel AFR Gauge) 30-0300

WIDEBAND UEGO AIR/FUEL CONTROLLERS AEM PN: 30-0300
Patented X-Digital Technology - The fastest responding wideband in independent testing

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

Specs & Features

• X-Series Wideband UEGO AFR Controller Gauge were fastest responding wideband air/fuel ratio controllers in an independent test vs. 17 competitors wideband AFR controllers
• Patented X-Digital wideband technology (Patent 9,575,030)
• AEM codeveloped the new sensor with global automotive supplier FAE, culminating in a new sensor design that has a faster response time than the Bosch 4.9 LSU and is less prone to failure in high performance vehicles
• Factory calibrated resistor does not require free-air calibration, but technology allows for free-air calibration as sensor ages if user desires
• Compatible with vehicle/system voltages up to 16V
• 0-5V & RS232 output for data logging and feedback control, AEMnet (CANbus) for data logging and daisy-chaining multiple controllers up to 16 cylinders
• Can display AFR values in hundredths of a %
• 52mm gauge diameter and slim 0.825" gauge depth
• Gauge cup depth only .200" deep
• Auto dimming feature
• User configurable display via buttons on the gauge face for changing AFR values, Lambda and O2%, and 3- or 4-digit display
• Black bezel and black dual faced faceplate included (gauge only, silver bezel/white gauge option sold separately, PN 30-0300-ACC)
• Locking connectors

Product Description

AEM’s X-Series Wideband UEGO Air/Fuel Ratio Sensor Controller Gauges are built upon unique, patent-pending X-Digital technology that makes them the fastest responding wideband air/fuel ratio controllers in independent testing against 17 other wideband UEGO air/fuel controllers*.

The X-Series Wideband UEGO AFR Sensor Controller Gauge (PN 30-0300) measures 2 1/16th-inch (52mm) in diameter, and features a modern, visually striking faceplate and new seven-segment center display that is 87% larger than the 30-4110 AEM Wideband Gauge’s center display. This creates the perception of a larger overall gauge, but in a common 52mm size for easy mounting. Its slim depth (less than one inch overall) and ultra slim cup depth of .200-inches dramatically increases its application base and potential mounting locations.

The X-Series Wideband UEGO AFR Gauge has a user configurable display via buttons on the gauge face that allow you to change AFR values for different fuels, Lambda or O2%, change the center display to three or four digits, perform a free-air calibration if desired as the sensor ages, and change the CAN message ID when linking multiple X-Series Inline Controllers or X-Series Controller Gauges. A black bezel and black dual-faced faceplate for air/fuel and Lambda are included, and an optional silver bezel with white dual-faced air/fuel and Lambda faceplate is available (PN 30-0300-ACC, sold separately). An Auto Dimming feature is included. Locking connectors ensure a positive connection between the harnesses and gauge and a new single board design adds to the new gauge’s durability.

The gauge includes a 0-5v and RS232 Serial Port output for feedback control and data logging, and an AEMnet (CANbus) output for data logging. AEMnet allows additional X-Series Wideband Controllers to be daisy chained together (up to 16 cylinders) for recording AFR in multiple cylinders. It supports vehicle/system voltages up to 16V, and can be used on EFI or carbureted applications, and dynamometers in applications using gasoline, methanol, ethanol, Diesel, propane and CNG.

Customer and User Feedback

The AEM 30-0300 X-Series Wideband UEGO Air/Fuel Ratio Controller Gauge has received overall positive feedback from users, particularly for its ease of installation, accuracy, and high-quality construction. Many users note that the gauge provides clear, readable displays, especially with its large 7-segment center display, which enhances visibility. The user-configurable display options, such as switching between AFR and Lambda readings, as well as adjusting the number of digits, are frequently mentioned as valuable features.

Installation Tips and DIY Insights:

• Wiring: Users recommend following the straightforward wiring instructions, ensuring proper connections to the 12V power and ground. A common tip is to connect the ground wire to the ECU's signal ground rather than the main ECU ground to avoid potential ground loop issues.
• Sensor Placement: The wideband oxygen sensor should be installed in the exhaust system according to the manufacturer’s guidelines. Placement near the header or exhaust manifold is suggested for more accurate readings.
• Calibration: Though factory-calibrated, some users suggest performing a free-air calibration after installation or periodically to maintain sensor accuracy. This involves exposing the sensor to fresh air and following the calibration steps in the manual.

Some users have encountered issues with the provided sensors failing after some use, with a few opting to replace the AEM sensor with a Bosch 17025 sensor, which seems to improve reliability. Additionally, the gauge’s robust construction, including weatherproof connectors, is appreciated, as it helps with durability in varied environmental conditions.

Overall, the AEM 30-0300 is praised for its high-performance and ease of integration into both EFI and carbureted systems, making it a popular choice among car enthusiasts looking for precise air/fuel ratio monitoring.