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Published Apr. 29, 2019

Wideband gauges are designed to measure the air-fuel ratio in a vehicle’s internal combustion engine. They’re a special kind of air/fuel ratio gauge (also known by the acronym AFR gauge), developed for greater accuracy than the previously used ‘narrow gauge’ models. Installing a wideband gauge in your car brings a range of benefits – they help you keep an eye on the oxygen sensors, improve fuel economy, and reduce emissions. Overall, these highly accurate sensors are a boon to anyone who wants to tune a vehicle.

If you think your vehicle could benefit from a wideband O2 sensor and gauge, there are a lot of options. With so many devices to choose from, working out exactly which gauge is right for your car can be a real challenge. Luckily, we’re here to help – we’ve put together this list of the best wideband gauges on the market right, helping you to make an informed decision. We’ve also compiled a handy buying guide, so you can get the most out of this handy piece of kit.

The Best Wideband Gauge

Kicking off our list is this AEM wideband gauge. Featuring an easy to read LED display, and color changing ‘needle’, the handy device makes it easy to keep track of the changes from rich to lean in your car’s engine. Thanks to its 52mm housing, the versatile gauge will fit into the majority of gauge pods. The display itself can be remotely mounted almost anywhere in the vehicle, helping drivers or navigators to keep an eye on fuel ratios.

Every AEM gauge features a 0-5V analog output, compatible with data loggers and practically any engine management system. In use, it’s highly responsive and accurate, thanks to a Bosch UEGO sensor housed inside. The gauge also features interchangeable faceplates and bezels, making it simple to achieve the ideal look for your car. To help you get started, the device comes with everything you’ll need for a hassle-free installation, including a weld-in bung.

Key Features
  • Wideband gauge kit, compatible with most vehicles
  • Easy to read LED display, with color changing ‘needle’
  • 52mm housing fits the vast majority of gauge pods
  • Display can be remotely mounted
  • Features a 0-5V output, compatible with data loggers and engine management systems
  • Bosch UEGO sensor inside is highly accurate and responsive
  • Interchangeable faceplates and bezels for easy customization
  • Brand AEM
  • Model 30-4110
  • Weight 14.1 ounces

Innovate Motorsports has also earned a spot on our list, thanks to this sleek and effective innovate wideband gauge. Featuring patented DirectDigital technology, the handy device can display a vehicle’s air to fuel ratio with precision and speed. The gauge can also calibrate your car’s O2 sensor, for maximum accuracy.

In place, the device offers two adjustable linear 0-5V outputs, which can transfer information to your data logger, or engine management system. For easy installation, the kit comes with everything you’ll need to get started, including a weld-on bung, programming cable, sensor cable, and a full manual. Once installed, the remote sensor is easy to read, featuring a bright LED display. Drivers say the gauge is accurate and reliable, noting that it’s simple to install, too. It’s the perfect option for drivers who want to keep an eye on their fuel ratio, and perform accurate tuning.

Key Features
  • Wideband gauge with a sleek design
  • Features patented DirectDigital technology
  • Displays air to fuel ratio with accuracy and speed
  • Able to calibrate  O2 sensors for improved accuracy
  • Includes 2 adjustable linear 0-5V outputs
  • Transfers information to your data logger or engine management system
  • Weld-on bung, programming cable, sensor cable, and manual included
  • Features an easy to read LED screen
  • Simple to install
  • Brand Innovate Motorsports
  • Model 3796
  • Weight 5 ounces

Earning its second spot on our list is AEM, with its X-series wideband sensor.  Its striking modern faceplate, and seven segment centre display make it easy to read on the go, while X-Digital technology allows the device to measure a wide array of outputs that other sensors can’t. For ease of use, its display is actually 87% larger than other options on the market, allowing drivers and navigators to glean an accurate reading as quickly as possible.

The gauge includes a 0-5V output port, for accurate data logging whatever device or engine management system is used. Thanks to its impressive response time, the gauge offers drivers a safe, powerful, and accurate tune. Users reported that the device warmed up much faster than many options on the market.

Key Features
  • Wideband Gauge featuring X-Digital technology
  • Striking, modern appearance
  • Seven segment centre display makes for easy reading on the go
  • Display is 87% larger than other popular models
  • Includes a 0-5V output port, compatible with data loggers and engine management systems
  • Fast response time
  • Quick to warm up
  • Highly accurate readings
  • Brand AEM
  • Model 30-0300
  • Weight 2 pounds

Innovate Motorsports has earned a second spot on our list with the impressive MTX-L Plus. The handy not only displays the engine’s air/fuel ratio, it can also provide feedback on the vehicle’s O2 sensors. Featuring a super fast analogue output speed, the gauge ensures that you’ll clearly see any changes to air/fuel ratio live, feeding this data through the ECU (engine control unit). Thanks to Bosch LSU technology, these readings are highly accurate.

The gauge is specially designed for high performance applications and forced inductions, too, making it a great option for racing vehicles. Thanks to the gauge’s 52mm diameter, it’s easy to swap faceplates and bezels for a fully customized appearance. Featuring a bright LED display, the air/fuel ratio it easy to read at a glance, for safe on the go monitoring.

Key Features
  • Wideband gauge featuring Bosch LSU technology
  • Monitors a vehicle’s O2 sensors
  • Super fast analogue output speed
  • Suitable for high performance applications and forced inductions
  • Standard sized faceplate is easy to switch
  • Bezels are interchangeable
  • Bright LED display for easy on the go reading
  • Highly responsive
  • Brand Innovate Motorsports
  • Model 3918
  • Weight 1.8 pounds

The next wideband gauge to earn a spot on our list is by Auto Meter. This handy gauge comes as part of a convenient kit, ensuring you have everything you need to set-up your new device. A wiring harness, weld-in bung, O2 sensor, mounting hardware, and detailed instructions are all included. Featuring a Bosch LSU sensor, the gauge provides excellent accuracy and an impressively quick response time.

Once in place, the gauge emits a 0-4V output, which can be transferred into the majority of data loggers, ECUs, and laptops running tuning software. If you don’t have access to a laptop, it’s easy to see your engine’s air/fuel ratio at a glance thanks to the bright LED display. This, along with a radial bar graph display, makes the data easy to see at a glance. This handy kit is compatible with almost all street cars and race cars, for impressively diverse usage.

Key Features
  • Wideband gauge kit, includes everything you need for a smooth installation
  • O2 sensor also included
  • Features a Bosch LSU sensor for excellent accuracy
  • Quick response time
  • 0-4V output is compatible with most data loggers, ECUs, and laptops running tuning software
  • Bright LED display and radial bar graph display for easy reading at a glance
  • Compatible with the majority of street and race cars
  • Brand Auto Meter
  • Model 4379
  • Weight 1.55 pounds

Innovate Motorsports has earned a third and final spot on our list with this sleek and stylish wideband gauge. This industry leading gauge is one of the most accurate, and quickest to respond, on the market, making it the perfect option for high performance engines. The gauge features a modular design, making it easy for drivers to add additional tuning components as part of an MTS (modular tuning system).

Featuring two analogue outputs, the detectors can be hooked up to data loggers, ECUs, and laptops without unplugging the gauge itself. For an all-round better tuning experience, each gauge also includes tuning software for your laptop. Finally, the gauge looks good – its sleek blue and black design features a bright LED screen, which is simple and easy to read at a glance. When powered down, the faceplate assumes a discrete ‘blackout’ appearance, managing to avoid any gaudy colors. Users say that the kit works perfectly and has a durable design that’s built to last.

Key Features
  • Sleek design ‘blacks out’ when not switched on
  • Industry leading design is among the most accurate and most responsive on the market
  • Modular design makes it easy for drivers to fit additional tuning components
  • 2 analogue outputs accommodate a data logger, ECU, or laptop without unplugging the gauge
  • Laptop tuning software included
  • Durable design
  • Brand Innovate Motorsports
  • Model 3795
  • Weight 2 pounds

GlowShift also impressed us with its versatile and affordable wideband AFR gauge kit. As the only option on our list to feature a fully analogue display, it offers a vintage flair that’s especially at home in classic vehicles. This display can be had in 10 different colors ranging from subdued blue to bright purple. Thanks to a handy dimmer wire, the gauge’s brightness can be adjusted to prevent distraction in darker conditions.

The display itself reads from 10.0 to 20.0 AFR, providing the wide output range you need for accurate tuning and monitoring. The kit also features a second analogue output, perfect for data loggers and ECUs. When the AFR reaches a pre-programmed high or low point – set by you – the gauge will emit a an audio-visual warning to let you know. Each gauge comes with mounting hardware, and easy to follow installation instructions, for a smooth set-up process. It also includes a one year limited warranty, so you can rest assured it’s built to last.

Key Features
  • Wideband gauge kit with fully analogue display
  • Available in 10 striking LED colors
  • Dimmable display prevents distractions in dark conditions
  • Display reads from 10.0 to 20.0 AFR
  • Second analogue output is ideal for data loggers and ECUs
  • Audio-visual warnings let you know when the AFR reaches a pre-set level
  • Mounting hardware and installation instructions included
  • 12 month limited warranty included
  • Brand GlowShift
  • Model GS-ET02W
  • Weight 2.65 pounds

Making its third and final entry onto our list is AEM with this convenient combo set. The set features both a wideband gauge and a boost gauge, making it the perfect option when it comes to tuning turbo charged vehicles. Both devices are highly accurate, and easy to read, featuring a bright LED display with both numerical values and a sliding ‘needle’. The AFR gauge has an output of 0-5V, which can be easily connected to data loggers and ECUs. For added convenience, the device never requires air sensor calibration.

Both gauges come with everything you’ll need for a quick and simple installation, including interchangeable bezels and weld-in bungs. Both faceplates are also interchangeable, making it easy to customize your device. The boost gauge itself features a readout range of -30 to 35 PSI, for accurate pressure monitoring at all times. It also produces a 0-5V output, which can be hooked up to virtually any engine management system or data logger.

Key Features
  • Combo set including 1 wideband gauge and 1 boost gauge
  • Ideal for turbo vehicles
  • Highly accurate
  • Easy to read LED display with numerical value and sliding ‘needle’
  • Both gauges feature an output of 0-5V, ideal for data loggers and EMS
  • No air sensor calibration required
  • Interchangeable bezels and weld-in bungs included for easier installation
  • Standard sized faceplates are also interchangeable
  • Brand AEM
  • Model 30-4110 + 30-4406
  • Weight 2.55 pounds

Last, but not least, comes this digital wideband gauge from Auto Meter. The kit includes everything you’ll need for a fast and effective installation, including an eight foot wiring harness, stainless steel weld-in bung, mounting hardware, and detailed instructions. Once in place, the gauge provides responsive and accurate air/fuel data, thanks to a reliable and sensitive Bosch LSU sensor.

The device provides an output of 0-4V, which can be easily connected to data loggers, engine management systems, or laptops running tuning software. This great versatility makes for simple and accurate tuning. The gauge is customisable, too – users can program their own specifications for lean, rich, and Stoic air/fuel ratios, and receive a visual alert when the reading enters each range. Thanks to a bright LED display, featuring both numerical data and a sliding gauge, it’s easy to work out a vehicle’s AFR on the go with only a glance.

Key Features
  • Wideband gauge kit includes everything you’ll need for installation
  • Provides responsive and accurate data thanks to a Bosch LSU sensor
  • Features an output of 0-4V, compatible with data loggers, EMS, and laptops running tuning software
  • User programmable rich, lean, and Stoic ranges
  • Bright and clear LED display with numerical data and a sliding gauge
  • Simple, attractive appearance
  • Brand Auto Meter
  • Model 4378
  • Weight 1.2 pounds

Best Wideband Gauge Buying Guide

These wideband gauges are among the best on the market right now, and we’re confident you’ll find the perfect option for your needs somewhere on the list. To help you work out which option is right for you, and get the most out of your new gauge, we’ve put together this handy guide. Below we run through some important information about wideband gauges, how to select one, and how to get the most out of it.

What is a Wideband Air/Fuel Gauge?

Since the internal combustion engine’s earliest days, over a century ago, tuning has been an important practice for maximising power output and efficiency. In previous years, tuners would use vacuum gauges, CO meters, and even attempt to ‘read’ spark plugs. However, these methods were often inaccurate, and tuning was considered to be more of an art than a science.

Wideband gauges are a device that was developed to address this important issue. These gauges measure the ratio of fuel to oxygen exiting an engine’s exhaust, using highly accurate ‘wideband’ oxygen sensors. This data is fed into a computer system via electronic signals, which is interpreted into a clear numerical figure that appears on the gauge display. At the same time, data can be channeled from these wideband sensors to the ECU, which subsequently determines the optimal fuel/air mixture for good efficiency and lowered emissions.

Coolant and gas

Things to Consider When Buying Wideband Gauges

If you decide to install a wideband gauge in your vehicle, there are few factors to bear in mind:

  • Compatibility

It’s important to ensure that a wideband sensor is compatible with your vehicle and other equipment. Many can be connected to existing ECUs, EMS, and data loggers, thanks to an extra output port. Outputs from a wideband gauge usually range from 0-4 volts.

  • Display

Wideband gauge displays are quite diverse in appearance, giving you the option to choose a display that’s easy to see. Look out for adjustable brightness, anti-glare protection, and a ‘needle’ style display that’s easy to read at a glance.

  • Accuracy & Responsiveness

Wideband gauges are at their most useful when they can measure and convey the air/fuel ratio quickly and accurately. Although it’s difficult to tell how well a gauge will work prior to installation, it’s a good idea to watch out for Bosch sensors, as these are typically a high quality component. Checking for feedback from other customers can also provide plenty of insight into the device’s performance.

  • Extra Features

Some wideband gauges come as part of a set, such as number nine on our list. This AFR gauge is accompanied by a boost gauge, making it an excellent option for vehicles fitted with turbo chargers. Other features to look out for include interchangeable faceplates and bevels, automatic air sensor calibration, and the inclusion of tuning software.

Benefits of Using a Wideband Air/Fuel Controller

Using a wideband gauge to keep track of your engine’s air/fuel ratio comes with a range of benefits, including:

  • Wideband gauges are ideal for diagnostic purposes
  • Wideband gauges are ideal for engine calibration purposes
  • Using a wideband gauge allows for more accurate
  • Wideband gauges can display live data about the AFR to your dashboard
  • Certain wideband gauges can be set up to automatically adjust AFR for optimum performance
  • The majority of wideband gauges are quick and simple to install in many vehicles

How to Calibrate Your AFR Gauge

The exact calibration process will vary between devices, but usually consists of the following steps:

  • Disconnect the O2 sensor cable, and unbolt the sensor from the O2 bung
  • Power the vehicle’s electronics by turning the key to the ‘on’ position
  • Wait at least 30 seconds
  • Turn the key to the ‘off’ position, before reattaching the sensor to its cable
  • Power up the electrical system with the sensor in free air (ie. not in the exhaust)
  • Wait for the display to read ‘CAL’
  • Power the electrical system down once again, before reconnecting the sensor to the exhaust system

For naturally aspirated cars, recalibrating around once a year should be sufficient. For forced induction vehicles, this should be increased to twice each year, while race cars running on leaded fuel should recalibrate these sensors every week.

Car Instrument Panel Close Up

How to Get the Maximum from Wideband Sensors

Wideband sensors are a complicated piece of equipment, but even naive tuners can get the most out of them with these tips:

  • Be sure to calibrate oxygen sensors on a regular basis, to maintain greater accuracy
  • Place the sensor at least 24 inches downstream from the cylinder head exhaust ports
  • Recalibrate the sensors if your vehicle experiences altitude changes of 5,000 feet or more – different air pressure means different oxygen concentrations

Our Top Pick

For us, the best air fuel ratio gauge on the market right now has to be this versatile and affordable option by AEM. Thanks to its Bosch UEGO sensor, the device can display live data with excellent precision and accuracy. It’s simple to install, too, with 52mm housing that fits into most gauge pods. For a hassle free installation process, the kit includes a weld-in bung, helping drivers to get their new gauge up and running in no time.

Once in place, the gauge display can be mounted almost anywhere in the car. It also features interchangeable faceplates and bezels, making it simple to achieve the look you want. Thanks to its LED display, featuring a color changing ‘needle’, the display makes it easy to see when your fuel ratio fluctuates from rich to lean. The gauge also features a 0-5V output, that’s compatible with most data loggers, and the majority of engine management systems. Drivers across the board were impressed with the quality and accuracy – especially considering its budget friendly price point.


  1. How does the oxygen sensor in a car work? – HowStuffWorks