During normal operation, a typical HEV engine will start and stop more frequently than a regular gasoline engine. This repeated action over thousands of miles between services can cause the additives in the oil to breakdown allowing carbon, sludge, and other deposits to build up in oil passages and embed on piston rings.

To make matters worse, the small, high-output HEV engines are extremely sensitive to fuel deposits that can build up on fuel injectors, intake valves and ports, and in combustion chambers. Even the smallest amount of deposits can increase exhaust emissions, reduced fuel economy, and cause drivability problems.

The unique operation and design of these vehicles require a different maintenance process with specialized cleaners and procedures during a service visit to restore and/or maintain optimal performance.