Why do people tamper?
Some people still believe that tampering with a car’s emission controls will improve the vehicle’s performance. Changing the manufacturer’s recommended settings for the engine may actually reduce fuel efficiency. Today’s automakers design cars to meet the best possible balance between performance, mileage and low emissions. Most vehicles in Pennsylvania will be required to undergo some sort of check for tampering: 1996 and newer vehicles in 17 counties are required to have on-board diagnostics tests which by their nature will detect tampering; 1995 and older vehicles in 25 counties with separate emission inspections are required to have visual checks of the catalytic converter, exhaust gas recirculation (EGR) valve, positive crankcase ventilation (PCV) valve, fuel inlet restrictor, air pump and evaporative control system components. Inspectors will check for their presence, whether they are properly connected and whether they are the appropriate type for the vehicle. a similar visual c
