Effects of Gasoline and Ethanol Fuel Corrosion Inhibitors and Fuel Detergents on Powertrain Intake Valve Deposits

Corrosion inhibitors (CIs) have been used for years to protect the supply and distribution systems used for transportation of fuel from refineries. They are also used to buffer the potential organic acids present in an ethanol blended fuel to enhance storage stability. The impact of the types of inhibitors on spark-ignition engine fuel systems, specifically intake valve deposits, is known and presented in open literature. However, the relationship of the corrosion inhibitors to the powertrain intake valve deposit performance is not understood. This paper has two purposes: to present and discuss a survey of corrosion inhibitors and how they vary in concentration in the final blended fuel, specifically E85 (Ethanol Fuel Blends); and to show how variation in concentration of components of CIs and detergents impact intake valve deposit formation. Commercially available corrosion inhibitor packages and detergent packages for both gasoline and ethanol blended fuels, specifically E85 fuels (Ethanol Fuel Blends), were studied for their impact on intake valve deposit formation in a naturally aspirated port fuel injection (PFI) engine.