Fuel Measurements Obtained by Engine Tests Using Unique Methodology Validated by Other Methods: Part of the fuel injected into an intake port adheres to the walls of both the intake port and cylinder especially when the engine is cold. This fuel that adheres to the walls causes hydrocarbon emissions to increase during cold start. To develop technology to reduce cold-start emissions, detailed information about the amount of fuel adhering to the walls should be valuable for engine designers. Engineers at Nippon Soken and Toyota Motor Corporation developed a technique to quantitatively measure the amount of fuel adhering on both intake port and cylinder walls and reported their measurement methodology and engine test results. A 0.6-liter single-cylinder engine was prepared to trap and vaporize fuel in both the intake system and cylinder and to operate similarly to a 2.4-liter four-cylinder engine in terms of intake pressure and speed during cold start. The test procedure was somewhat complicated; however, the measurement results were repeatable with a reasonable level of measurement error and validated with two other methods to determine the amount of fuel burned in the engine. The chapter consists of 13 pages including 13 figures and 2 tables.