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AEM

AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge

  • Based on 2,217 reviews
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Availability: 12 left in stock
Fulfilled by HNR Global Auto Parts

Arrives Sep 30 – Oct 1
Order within 16 hours and 49 minutes
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Features

  • The X-Series wideband UEGO AFR sensor controller gauge (PN 30-0300) features a modern, visually striking faceplate and new seven-segment, center display that is 87% larger than the 30-4110 AEM
  • 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
  • X-Digital wideband technology gives these controllers the ability to read and report values that other controllers do not, which can deliver more optimized engine tuning and a safer overall operating condition
  • Faster response time improves wideband feedback control, and can provide a safer, more powerful and accurate tune
  • When tuning an engine using wideband AFR feedback control on an inertia dyno, dead time affects the data you are looking at because it is reported in a different operating location than when it actually occurred

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.

Specs & Other Info

SpecificationDetails
BrandAEM
Construction MaterialDurable Plastic
Weight of Item1.43 pounds (0.65 Kilograms)
DesignContemporary
Accuracy of MeasurementSuperior
Installation MethodFlange Mount
Primary UseTimekeeping
ManufacturerAEM
Product Model30-0300
Origin of ManufactureChina
Product ExteriorFinely Machined
Manufacturer & OEM Part Number30-0300
Release DateNovember 18, 2015
Current StatusNot Discontinued

Frequently asked questions

The AEM X-Series UEGO Gauge is a tool used to monitor and display the air/fuel ratio (AFR) of your vehicle. This is essential for tuning and optimizing your engine performance. It ensures that your engine runs at the best efficiency, resulting in better fuel consumption, more power, and less potential for damage.

The AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge is versatile and can be used with most vehicles that have an On-board Diagnostics (OBDII) port. However, before purchasing, it's always recommended to check if your specific vehicle model is compatible with this device.

The AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge is known for its excellent accuracy. It uses Bosch 4.9 LSU wideband UEGO sensor and the fastest controller technology in a 52mm gauge providing real-time AFR values with less than 100 millisecond response time.

The AEM X-Series UEGO Controller Gauge is generally easy to install with appropriate mechanical experience. The package includes a complete installation manual with step-by-step instructions. However, if unsure, it's recommended to have it installed by a professional to avoid any potential damage.

Top Amazon Reviews

🚀 Abunda's Overview

This is our summary and key points to consider based on customer reviews.


These reviews suggest that the product is exceptional for fine tuning engines, enhancing power, and improving overall vehicular performance. It seems convenient to install, works great after initial adjustments and provides good value for the price. Note that some users have reported issues with the bezel and recommend testing the product immediately following purchase.

Pros

  • 🔥 Considerably enhances engine performance.
  • 🔧 User-friendly installation process.
  • 💰 Provides good value for money.
  • 💡 Allows for precise tuning.

Cons

  • 😕 Some users found the bezel thick, causing aesthetic concerns.
  • ☝️ Needs immediate testing after purchase to ensure perfect functionality.
  • 🎨 Matte finish of the bezel didn't match with most interiors which may require additional modification (like painting).

Should I Buy It?

Based on the high ratings, user satisfaction, and multi-functional use, it is recommendable to purchase the product assuming the minor concerns raised aren't significant hindrances. It appears to deliver excellent results in terms of tuning and boosting performance, thereby making it a valuable addition to your automotive toolbox.


  • Legit AEM X series AFR gauge assembly with the correct verified sensor as advertised on AEM website.
After reading the different reviews I was still skeptical about ordering. I said what the heck it’s Amazon and if anything looks out of norm back it will go. Well I received it the day after I bought it so less than 24 hours at no extra cost because of prime, and I must say it is the real deal! The security tape was intact all parts packaged like they are supposed to be, I took a picture of the sensor and verified it and all the parts using chat gpt and everything is completely legit.. so all the other people either don’t know what their looking at or they are unable to identify fake from real. If you’re-wanting the new x series so you can dial your AFR in and get the most out of your engine safely then buy this gauge. I promise it’s worth the extra not to have to worry abt a crap sensor. Thank you Amazon another great delivery! ... show more
Reviewed in the United States on September 5, 2026 by Alcohol runner

  • Aem for the win
No issues, straight forward install. 17 sierra
Reviewed in the United States on May 20, 2026 by Kevin cossey

  • Perfect
Perfect original item
Reviewed in the United States on June 28, 2026 by Christian Slater Knox

  • It’s the real deal 👍🏼
I’m writing this for people on the fence about whether it is the real AEM gauge/sensor or not. It is, I went to AEM’s website and compared the part numbers and pics and it is exactly the same. I installed it per instructions and warnings and it is working perfectly. It’s a good deal and a great product. ... show more
Reviewed in the United States on November 6, 2025 by William B.

  • can’t go wrong w aem
don’t know a single soul that’s had a bad experience with a aem wideband… plus you get a sticker
Reviewed in the United States on September 5, 2026 by Nathan

  • Wow!!! That was fast!
Wow, I ordered an AEM Wideband late Sunday evening on July 13th and when I ordered it said that it would arrive Saturday. The next mourning I checked it and it had shipped but was still set for arrival on Saturday. Today I get a notice saying that something had changed so I clicked on it and My Wideband Sensor had already arrived at 12:30. I couldnt believe it. Ive never had anything that Ive ordered ever come in that fast. As far as the product it looks and works perfect. ... show more
Reviewed in the United States on July 15, 2025 by Paco

  • Works but 02 doesnt last
Gauge works great but 02 sensor went bad after 2 uses and isnt covered under warrant recommend gettin the actal bosch o2 sensor
Reviewed in the United States on March 26, 2026 by Nathan Morrisett

  • Excellent product
Highly recommend this product, I installed on 95 firebird
Reviewed in the United States on June 2, 2026 by Jessee

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