Saul "The Surgeon" Gutierrez...
Saul "The Surgeon" Gutierrez of Extreme Automotive in Canoga Park, California, seats the Bosch Universal Exhaust Gas Oxygen sensor for AEM's analog wideband air/fuel ratio gauge (PN 30-5130; $242.35), in the passenger-side exhaust tube on Chris McCollum's supercharged, '04 Mustang GT. While a bung (it requires welding) for the O2 sensor also is included with the gauge kit, Chris' Pony saw plenty of time on Extreme's chassis dyno prior to our project. A bung for a wideband sensor was already in the tube.
Each year, your tech editor spends one full week in January at a gathering called the Motorsports Parts Manufacturers Council Media Trade Conference.
Held in Los Angeles, MPMC gives members of the performance-automotive media an opportunity to sit face-to-face with representatives from several performance-parts manufacturers to discuss their new products. Often we make arrangements to do projects that include installing and testing some of these products for the technical reports that you read each month here in 5.0 Mustang & Super Fords.
In our 2009 audience with AEM, we were shown a variety of products that all are applicable to late-model, EFI Mustangs; items such as the company's engine-management systems, water-methanol-injection kits, cold-air- induction pieces, and digital/analog gauges. While all of the offerings were impressive, we chose to focus on AEM's wideband O2 sensor. It's a good idea for a Tech Inspection given the current state of enhancing power in street-driven 'Stangs-by way of blower and turbocharger-and how critical a combination's air/fuel ratio is to the overall efficiency of a boosted application.
AEM's wideband air/fuel gauge...
AEM's wideband air/fuel gauge kit includes all that you see here: a 2 1/16 analog gauge assembly (we're using the black-faced unit, but a white-faced gauge is also available), a Bosch UEGO sensor, an installation kit with an O2 bung and electrical connectors, an eight-pin power harness, and a six-pin sensor harnes
We all know how cool and slick-looking the digital gauges are (and AEM does have a complete lineup of digi-gauges for air/fuel, boost, and other engine-system monitoring), but we chose the traditional gauge (PN 30-5130; $242.35) for installation on Chris McCollum's '04 Mustang GT. Chris' blown 'Stang has been on the dyno many times, using the dyno's wideband for calibrating the ratio. When a fuel-pressure gauge went on the fritz, we seized the opportunity to install AEM's analog instrument, which will let Chris know the quality of "the burn," when he's cruising the streets of L.A.'s San Fernando Valley or blasting down the freeway with the pedal planted.
AEM's wideband air/fuel gauge is easy to install, easy to read, and accurate within' 0.1 AFR, thanks to the included Bosch wideband O2 sensor.
Saul "The Surgeon" Gutierrez of Extreme Automotive put the pieces in place for this quick exercise (as you'll see in the accompanying photos). Any mechanically adept 'Stangbanger can do the same right in the driveway, provided a welder is handy for installing the included bung for the sensor.

After connecting the O2 sensor...

After connecting the O2 sensor to its six-pin harness and securing all of the wires so that they remain clear of the driveshaft, exhaust, transmission, and such, Saul then snaked the connector and wiring for the sensor harness up through the shifter boot and into the Pony's cabin.

Once the sensor harness is...

Once the sensor harness is routed to the location where the gauge is being mounted (we're placing it in an A-pillar gauge pod), Saul takes both the sensor harness and the eight-pin power harness and plugs them into their appropriate receivers in the gauge, and then sets the gauge inside the pod, before moving on to connecting wires.

AEM takes every bit of guesswork...

AEM takes every bit of guesswork out of wiring the air/fuel gauge by labeling each wire with its purpose/final destination (power, ground, lights/dimmer circuit, data logger, and so on). Notice there are two power (red) and ground (black) wires. They're for the power and sensor harnesses, respectively, and can be tied together (red + red/black + black), and tapped into a constant 12-volt source and common ground. Wiring power and ground this way ensures that the needle on the gauge will "park" upon powering down.

Saul uses a test light to...

Saul uses a test light to locate a constant 5-amp fuse for the gauge's power wires. The pink wire from the harness requires a switched (hot-with-the-key) 12 volts, also 5 amps, which Saul also finds during this process.

With the gauge fully installed...

With the gauge fully installed (in completing this part of the project, Saul refits the driver-door weatherstrip, and pops the A-pillar gauge pod and kick panel in place) and the 'Stang's engine running at an idle, we see that everything functions as it should, with air/fuel registering at about 14.7:1, and accurate to about 0.1 AFR of the info that the dyno itself recorded. We selected red (white, blue, green, orange, light blue, and aqua also are available) as the hue for our illumination, which works well with the Mustang's Laser Red body color. The gauge also features two status lights that let Chris know when there is a problem that requires getting out of the gas before things get messy under the hood.