TEXAS EMISSIONS INSPECTIONS FINAL PAPER
2026 QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◉ Largest source of air pollution in Texas. Answer: Motor vehicles
◉ Main pollutants from motor vehicles. Answer: Hydrocarbons (HC)
and Carbon Monoxide (CO).
◉ Purpose of the OBD II system. Answer: To monitor emissions-related
components and alert the driver of malfunctions.
◉ Vehicles required to have OBD II inspection. Answer: Gasoline-
powered vehicles 2-24 model years old.
◉ Vehicles exempt from OBD II testing. Answer: Diesel vehicles,
motorcycles, electric vehicles, and vehicles over 24 model years old
◉ What are "affected counties"? Answer: Counties required to
participate in the emissions inspection and maintenance (I/M) program.
, ◉ rimary emissions inspection method in affected counties. Answer:
OBD II inspection
◉ What does the OBD II system monitor? Answer: Emission control
systems and components
◉ What triggers the MIL? Answer: An emissions-related malfunction
detected by the OBD II system
◉ Another name for the MIL. Answer: Check Engine Light
◉ Required MIL status to pass inspection. Answer: Off or not
commanded on.
◉ Does the "Maintenance Required" light cause a failure? Answer: No
◉ When is the MIL checked? Answer: With the engine running.
◉ What are Diagnostic Trouble Codes (DTCs)? Answer: Codes stored
by the OBD II system that indicate faults.
◉ Does the presence of DTCs automatically fail a vehicle? Answer: No,
only if the MIL is commanded on
2026 QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◉ Largest source of air pollution in Texas. Answer: Motor vehicles
◉ Main pollutants from motor vehicles. Answer: Hydrocarbons (HC)
and Carbon Monoxide (CO).
◉ Purpose of the OBD II system. Answer: To monitor emissions-related
components and alert the driver of malfunctions.
◉ Vehicles required to have OBD II inspection. Answer: Gasoline-
powered vehicles 2-24 model years old.
◉ Vehicles exempt from OBD II testing. Answer: Diesel vehicles,
motorcycles, electric vehicles, and vehicles over 24 model years old
◉ What are "affected counties"? Answer: Counties required to
participate in the emissions inspection and maintenance (I/M) program.
, ◉ rimary emissions inspection method in affected counties. Answer:
OBD II inspection
◉ What does the OBD II system monitor? Answer: Emission control
systems and components
◉ What triggers the MIL? Answer: An emissions-related malfunction
detected by the OBD II system
◉ Another name for the MIL. Answer: Check Engine Light
◉ Required MIL status to pass inspection. Answer: Off or not
commanded on.
◉ Does the "Maintenance Required" light cause a failure? Answer: No
◉ When is the MIL checked? Answer: With the engine running.
◉ What are Diagnostic Trouble Codes (DTCs)? Answer: Codes stored
by the OBD II system that indicate faults.
◉ Does the presence of DTCs automatically fail a vehicle? Answer: No,
only if the MIL is commanded on
