Part Type: Accessory Drive Belt Idler Pulley. 1988 Chevrolet S10 Engine: 4.3L V6 GAS; With A.C.; OE Washer Not Required;. 1989 Chevrolet S10 Engine: 4.3L V6 GAS; With A.C.; OE Washer Not Required;. 1990 Chevrolet S10 Engine: 4.3L V6 GAS; With A.C.; OE Washer Not Required;.