O2 Sensor for Air/Fuel Meter

The FAST Electronics O2 Sensor for Air/Fuel Meter (Model 170408) is a wideband oxygen sensor designed specifically for EZ-EFI and aftermarket air-fuel ratio monitoring systems. This replacement sensor delivers real-time exhaust oxygen data essential for precise fuel mapping and engine tuning on carbureted and fuel-injected engines running custom fuel management systems.

Wideband oxygen sensors operate across a wider range of air-fuel ratios than conventional narrowband designs, providing more granular feedback across the entire operating envelope—from lean cruising to rich wide-open-throttle conditions. This extended measurement range makes wideband technology the standard for serious tuning work, dyno testing, and street performance applications where fuel curve optimization directly impacts both power delivery and fuel economy. The sensor integrates seamlessly with FAST EZ-EFI systems and compatible aftermarket air-fuel meters, allowing tuners to log live lambda values and adjust fuel tables with confidence.

This sensor is essential for engine builders, performance shops, and enthusiasts running standalone fuel injection or carbureted engines with closed-loop fuel control. Whether troubleshooting a lean stumble, validating a new intake manifold, or dialing in peak power on a modified engine, a quality wideband oxygen sensor provides the data needed to make informed tuning decisions. As an OEM FAST replacement part, it carries the fit and function specifications matched to FAST fuel management hardware, ensuring proper integration without adapter complications.