How can fuel quality affect emission test results?

Fuel quality plays a significant role in the performance of an engine and subsequently affects its emissions. Poor quality fuel often contains higher levels of impurities and may lack the appropriate additives needed for optimal combustion. This can result in incomplete combustion within the engine, leading to the production of increased unburned hydrocarbons and other harmful emissions, which can directly contribute to test failures during emissions testing.

The chemistry of the fuel affects how well the engine can burn it. With low-quality fuel, vehicles may experience issues such as knocking or misfiring, which further exacerbates emission problems. Additionally, poor fuel can increase carbon deposits in the engine, negatively impacting its efficiency and increasing exhaust emissions. As a result, using subpar fuel makes it more challenging for vehicles to meet the required emissions standards during testing.

Therefore, while high-quality fuel does not guarantee a pass, it significantly reduces the likelihood of failing an emissions test by promoting more complete combustion and lower emissions, demonstrating the critical impact fuel quality has on emissions results.