Gledewen Wideband UEGO Air-Fuel Ratio Gauge 52mm with LSU 4.9 Sensor — 20ms Response, RS-232 Output

Gledewen 30-0300 is a complete 52mm wideband UEGO air–fuel ratio gauge kit with LSU 4.9 sensor and controller for fast, accurate real-time AFR and lambda readouts.

This compact kit combines a reversible LED face 52mm gauge, LSU 4.9 wideband oxygen sensor, and wiring harness to give tuners and enthusiasts immediate feedback on combustion mixtures. It supports multiple display modes (AFR, Lambda, O2%), configurable precision, and both resistor-trim and free-air calibration options. With 0–5V analog and RS-232 serial outputs, it’s built to integrate with dataloggers and aftermarket engine management systems while operating on typical vehicle voltages.

How quickly and accurately does this gauge report air–fuel changes?

The Gledewen wideband uses an LSU 4.9 sensor and electronics tuned for rapid response, so you’ll see mixture shifts almost instantly. Typical response time is around 20 ms, making it suitable for live tuning and transient testing.

• LSU 4.9 sensor for fast, stable readings
• 20 ms typical response time for transient accuracy
• Display modes for AFR, Lambda, and oxygen percentage
• Configurable 3- or 4-digit precision for detailed monitoring

What connections and outputs are included for integration?

The kit provides a PWR/IO cable and sensor harness plus both analog and serial data outputs to link with external devices. You can tap the 0–5V analog output for gauges or data loggers and use the RS-232 serial stream for PC tuning tools or ECU interfaces.

• 0–5V analog output for third-party gauges and loggers
• Serial RS-232 output for PC/ECU communication
• Compatible with vehicle systems up to 16V
• Plug-and-play harnesses and included connectors simplify wiring

How do I install and calibrate the wideband gauge?

Mount the 52mm gauge in a standard hole, wire the red and black to 12V power and ground, then route the sensor cable and install the LSU 4.9 sensor into the exhaust bung. The instrument offers both resistor-trim (rCAL) and free-air (ACAL) calibration—rCAL is pre-configured on the supplied sensor for most users, eliminating the need for extra setup.

• Mount 52mm gauge; connect power (red) and ground (black)
• Install LSU 4.9 sensor in exhaust bung and connect harness
• Use rCAL (resistor trim) for factory-set accuracy or ACAL for free-air calibration
• On-dash buttons switch display modes and initiate calibration

What display and usability features help during tuning sessions?

The gauge face features a sweeping multi-color LED arc and a central numeric readout that is reversible for mounting flexibility. Auto-dimming preserves night readability while configurable display modes and decimal precision let you tailor the readout to your workflow.

• 24-color-coded LED arc for quick visual lean/rich cues
• Reversible faceplate for custom mounting orientation
• Auto-dimming for night driving and tunings
• Switchable 3- or 4-digit modes for coarse or fine readings

Who this is for: The Gledewen 30-0300 wideband UEGO kit is aimed at engine tuners, race teams, and performance enthusiasts who need precise, real-time mixture data and easy integration with aftermarket ECUs or logging systems. It’s also suitable for hobbyists and DIY mechanics who want a dependable sensor/controller combo with multiple calibration choices and straightforward installation.