As a STAR-certified Test Only station in Old Encinitas, A Plus Smog Test Only Center has processed California BAR emissions inspections from its Coast Highway 101 bay since 2002. The single-bay operation runs OBD-II and tailpipe-sniffer protocols required under California's Smog Check Program, and vehicles that need pre-inspection registration or VIN verification before testing can complete that paperwork at CJT Insurance, Vehicle Registration, VIN Verification elsewhere in the 92024 ZIP. The STAR designation from the California Bureau of Automotive Repair is a performance-based certification restricted to stations whose pass/fail accuracy meets the state's statistical threshold for emissions testing integrity. Vehicles directed to Test Only stations by the DMV's biennial selection process cannot be tested at standard smog-and-repair shops, though drivers needing both diagnosis and repair after a failed test often continue to STAR-rated full-service stations like Encinitas STAR Smog & Auto Repair for catalyst and oxygen-sensor replacement. The station's BAR-97 emissions analyzer measures hydrocarbon, carbon monoxide, nitrogen oxide, and carbon dioxide concentrations against CARB cut-point tables calibrated by model year, engine displacement, and fuel-delivery type.