BioGuard Plus 6 "provides diesel boaters everything needed in one formula to prevent all diesel fuel-related problems," says ValvTect Petroleum. The manufacturer markets it as a 6-in-1 product that prevents biological contamination, hinders corrosion, stabilizes the fuel, lubricates fuel pumps and injectors, prevents sludge, cleans injector deposits to improve performance and fuel economy, and reduces smoke, soot and emissions. A quart treats 375 gallons and retails for $39.99. ValvTect Petroleum, Northbrook, Ill., (800) 728-8258. www.valvtect.com
This article originally appeared in the May 2011 issue.