Fails Emission Test: Carbureted

Ensure engine is reaching normal operating temperature.
Ensure there are no vacuum leaks.
Check for correct PCV valve operation.
Check crankcase for gasoline contamination.
Verify vacuum hose routing is correct.
Verify choke is fully open after engine is warm.
Ensure fuel level is at specified mark on carburetor sight glass.
Verify correct carburetor idle and fuel mixture adjustment.
Verify base timing is correct.
Check EGR valve system.
Check operation of coolant temperature sensor.
Ensure fuel cap gasket is in good condition.
Check fuel tank filler tube for tampering of restrictor. If tampering has occurred, check catalytic converter for lead contamination.
Ensure exhaust system is not restricted.