This 4-wire narrow-band oxygen sensor fits select 1994-2003 Buick, Cadillac, Chevy, GMC and other applications and signals whether the exhaust is running rich or lean so the engine computer can trim fuel delivery. A built-in heater brings the element to operating temperature quickly after a cold start.

Walker Products 350-34525 Oxygen Sensor Features:

• Fits 1997-2000 Buick Century, Chevy Cargo Van, Malibu, Venture, Oldsmobile Silhouette, Pontiac Grand Am
• Fits 1997-2003 Buick LeSabre, Park Avenue, Regal, Chevy Monte Carlo, Pontiac Bonneville, Grand Prix; 1997-1999 Buick Riviera, Oldsmobile 88, LSS, Pontiac Trans Sport
• Also fits select Buick, Cadillac, Chevy, GMC, Oldsmobile and Pontiac applications
• Used in both upstream and downstream positions, depending on application
• 4-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 375 mm (14.8 in.) overall length
• Female square connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue