Used MAP sensor.  This is a MAP (Manifold Air Pressure) sensor, which measures intake manifold vacuum.  Fits the following:

88-92 TBI V8 Camaro and Firebird/Trans Am
90-92 TPI V8 Camaro and Firebird/Trans Am
93-97 LT1 V8 Camaro and Firebird/Trans Am  ***does not include seal
90-91 TPI Corvette
92-96 LT1 Corvette  ***does not include seal
90-95 3.1L/3.4L V6 Camaro and Firebird