RepairPal Certified shops can diagnose and repair your 2003 Nissan Altima. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Standing in front of car looking at the engine, cylinders are numbered > 1- 2- 3- 4 > left to right as shown... So # 4 is the one closest to the drivers side fender .. Thus # 1 is the one closest to the passenger side fender.