Part Number: 30-5130

Recently we had the opportunity to try out AEM’s new wideband Air/Fuel Gauge in our shop 996 Turbo. Having searched around we wanted to find the best balance between functionality, reliability, cost and aesthetics. Our search landed us right to AEM’s new analog wideband Air/Fuel gauge. The benefits of a quality wideband gauge in a car are many but for those that are a little new to this particular instrument let me answer a few questions:



What is a wideband air/fuel gauge?
A wideband Air/Fuel Gauge is an instrument that accurately displays the ratio of air to fuel in your engine. It typically reads how many parts of air to one part of fuel. For example a reading of 14.7 would translate into 14.7 parts of air to one part of fuel. It does this by using an additional oxygen sensor that samples the mixture.

Why do I need one?
Well the reasons are many but in short this sensor will accurately display how your car is running in regards to fuel mixture. You have heard people comment on if their car is running lean or rich...this is a tool used to find that out. The higher the number reads the leaner your car is running. The lower the number the richer your car is running. Tuners have been using these for years to help dial in a cars fuel mixture to optimize performance while retaining reliability and safety.

Why can’t I simply use a cheaper non wideband air fuel gauge?
The term wideband comes from the sensors sampling range. Standard air fuel ratio gauges piggyback the factory O2 sensor and translate it into a rough reading. The problem is that translation is done in the form of a vague colored light range. No actual number is given. Not to mention that factory sensor is a narrow band sensor. The factory sensor has a sampling range of 0-1 volts whereas a wideband sensor has a sampling range of 0-5 volts allowing it to be MUCH more precise. This would be like comparing a cup and a string to an actual telephone…night and day. The AEM system features a Bosch sensor with an accuracy of .1 AFR, making it among the fastest and most accurate widebands available.


Review:
What first drew us to the AEM line is there track record. We have been using AEM UEGO wideband digital gauges for years and its quite possibly the best all around wideband gauge. Easy installation, precise readings, quality construction all packed in a very aesthetically pleasing part. We knew this analog model would be just as accurate and well made.


Installation:
Step one in installing any gauge is determine where to mount it. We wanted a nice clean install that required no permanent modifications. We took a moment and looked at the dash layout from the driver’s seat to determine a good place to mount the gauges. I decided it was going to be best to remove the CD storage assembly and replace it with a custom carbon fiber panel. I removed the assembly and used it as a template to cut out the gauge panel with holes to house two gauges


Next we worked on power distribution for the AEM UEGO gauge. Using a multi-meter, we located constant power, switched power and dash lighting power in the fuse box. We routed the power wires from the gauge to the fuse box where I made the connections using Add-A-Line fused connectors. For ground, I connected directly to the dash frame using a nut and bolt.


We then moved on to routing the cable that connects the UEGO gauge to the O2 sensor. I removed the center counsel and ran the cable back and then under the rear carpeting to a factory grommet near the driver’s side rear passenger foot-well.


From there, We followed the brake and fuel lines up and over the motor to the area where the factory O2 sensors connect on the driver’s side. This would allow us to mimic the factory style (heat protected) routing for the AEM UEGO sensor. We marked the location on the exhaust where we wanted the bung for the UEGO sensor. We removed the exhaust, drilled a hole for the sensor and had one of our welders TIG weld the bung in place. With the exhaust reinstalled on the car, We installed the UEGO sensor and connected it to the cable leading back to the gauge. We took a moment to test the gauge and make sure all our connections were good before buttoning the car up. Overall I think the install came out very nice.

Performance:
With the gauge installed and the sensor hooked up its time to see how she works. The first thing that stands out is the color range, instead of choosing a predetermined color AEM actually has a fine dial on the back of the gauge. This allows you to dial in the color of the gauge to match your factory instruments. We was able to match the factory Porsche instrument cluster EXACTLY! It literally looks STOCK! This was a huge plus for us as we are very particular about how gauges match in a car. To top if off AEM even gives you two different bezel options (gloss black and silver) we chose black as it seemed to look the cleanest.

Below are some illuminated pictures from our shop BMW 335i


Now the real reason to buy a wideband A/F gauge is functionality. AEM does not disappoint! Most wideband A/F gauges on the market read primarily numerical. This is hard to read during real time as a series of numbers will rush by until it levels off. With an analog or needle based gauge you can watch the needs as it sweeps. This gives you a much better way of monitoring how A/F is changing in real time. With the needle you can see how fast the needle sweeps and if it dips or spikes. AEM actually developed this just for tuners so they can not only log and review A/F from the 0-5v output but also monitor it in real time. The needle is VERY responsive and smooth, so much it actually had me questioning the countless other needle based gauges that I have used in my car career. AEM got it PERFECT!

In summary we are very impressed with the AEM UEGO analog wideband air/fuel gauge. AEM never seems to disappoint with quality products that don’t break the bank. We plan on using other AEM gauges for our project 996t and we will continue to report back on them in the future. For more information or to pick up one of these for yourself visit us HERE