STP Super Concentrated Fuel Injector Cleaner contains concentrated detergents that help dissolve and remove harmful carbon, gum, and varnish deposits on fuel injectors. Without cleaning, deposits can lead to hard starts, lost acceleration and rough idling. This product is made with jet fuel, a high-quality carrier of active ingredients. Helps restore lost power and acceleration. Removes harmful deposits. Compatible with cap-less gas systems. STP Super Concentrated Fuel Injector Cleaner unclogs dirty fuel injectors to restore performance in just one treatment. Restore peak performance. Restore lost power and acceleration. Smooth rough idle and eliminate tough starts. Saves gas by cleaning fuel injectors and restoring lost fuel efficiency.