CNG

📖 YOUCANIC Automotive Glossary

CNG (Compressed Natural Gas) is an alternative fuel stored at approximately 3,600 PSI in high-pressure tanks, used primarily in fleet vehicles (buses, taxis, delivery trucks, government vehicles) and some consumer vehicles (Honda Civic GX, various bi-fuel conversions). CNG burns cleaner than gasoline, producing significantly less CO2, particulate matter, and NOx emissions. CNG vehicles use modified fuel injection systems with dedicated CNG injectors and fuel rails, high-pressure regulators that step down tank pressure to injection pressure, and CNG-specific ECU programming. Bi-fuel vehicles can switch between CNG and gasoline.

CNG system diagnostics involve the CNG control module, pressure regulators, tank pressure sensor, temperature sensor, and injectors. CNG-specific DTCs address fuel pressure, injector operation, and tank integrity monitoring. CNG tank inspection and certification is required every 3-5 years due to the extreme pressures involved — expired tanks must be removed from service. The YOUCANIC UCAN-II reads engine DTCs on CNG vehicles; CNG-specific module access depends on manufacturer support.