Alcohol/Contaminants-In-Fuel Diagnosis (Without Special Tool)

Water contamination in the fuel system may cause driveability conditions such as hesitation, stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector, at the lowest point in the fuel rail, and cause a misfire in that cylinder. If the fuel system is contaminated with water, inspect the fuel system components for rust, or deterioration.

Alcohol concentrations of greater than 10 percent in the fuel can be detrimental to fuel system components. Excessive alcohol in fuel may cause fuel system corrosion, deterioration of rubber components, and subsequent fuel filter restriction. Fuel with excessive alcohol may cause driveability conditions such as hesitation, lack of power, stalling or no start. Some types of alcohol are more detrimental to fuel system components than others.