FIAT 55353812. GMC 55353812, 93185493. OPEL 55353812, 855389, 9158718, 93185493. VAUXHALL 55353812, 9158718, 93185493. Engine Code: Z 18 XER; Construction Year to: 03/2010; Lambda Sensor: Regulating Probe; Fitting Position: before catalytic converter; for OE No.: 55353812; or; Engine Code: Z 18 XER; Construction Year to: 03/2010; Lambda Sensor: Diagnostic Probe; Fitting Position: after catalytic converter; or; Engine Code: A 18 XER; Construction Year from: 07/2010; Lambda Sensor: Diagnostic Probe; Fitting Position: after catalytic converter.