When the U.S. minimum additive performance standards were first established in 1995, many gasoline marketers reduced the concentration of detergent additive in market gasoline by up to 50%. As a result, many automakers experienced instances of deposit build up within engines leading to poor performance and sometimes engine damage, both resulting in dissatisfied customers.
Ten top automakers have raised the bar. TOP TIER™ Detergent Gasoline helps drivers avoid gasoline which may leave deposits on critical engine parts, reducing engine performance and in some cases, engine damage. That's something drivers and automakers can get behind.
Fuels with lower-quality additive packages can build up deposits on fuel injectors and on intake valves. Others can build up deposits in combustion chambers and may lead to intake valve sticking. These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness.
Retailers voluntarily join the program to supply a higher standard fuel which meets the TOP TIER™ requirements focusing on the engine needs which ultimately focuses on the end customer - the vehicle owner.
Unwashed gums are an indication of the detergency level in gasoline. In the United States regulation was passed in the late 1990s requiring a minimum level of detergency in gasoline. Following the introduction of this regulation, vehicle manufacturers experienced a significant increase in reported vehicle performance issues, leading to the introduction of the TOP TIER™ Detergent Gasoline program. The standard, developed and supported by automakers is based on engine performance.