misfueling

Misfueling is the act of fueling a vehicle or equipment with an incorrect type of fuel or with fuel from a different category. Examples include gasoline in a diesel vehicle, diesel in a gasoline vehicle, or using unapproved fuel blends. Misfueling is a common cause of engine and fuel-system damage and is often preventable.

Misfueling occurs across a range of settings, including passenger cars and motorcycles, commercial trucks, construction and agricultural equipment, aircraft, boats, generators, and lawn and garden tools. Many countries use color-coded fuel nozzles and separate fueling systems to deter misfueling, but errors can still occur, especially under stress or in unfamiliar environments.

Causes include human error, poor labeling, confusing or similar-looking fuels and connectors, fatigue, and distractions. In some cases, equipment employs dedicated fuels or restricted access to fueling points, but these measures do not always prevent mistakes.

Potential consequences range from poor performance and starting difficulties to severe damage. Misfueling can clog fuel filters, damage fuel pumps and injectors, impair lubrication, cause corrosion in fuel lines, and lead to warranty disputes or costly repairs. Contaminated fuel may also require disposal and remediation.

Prevention measures emphasize clear labeling and labeling consistency, color codes for fuels, physical design features to discourage wrong fueling, and training for operators and technicians. Anti-misfuel devices, standardized connectors, and validated fueling procedures can reduce risk. Always follow manufacturer recommendations and verify the correct fuel type before pumping.

If misfueling occurs, do not start or run the engine. Stop fueling, drain the contaminated fuel from the tank and lines if safe, replace filters, and have the system inspected and flushed by a qualified technician. Proper action can limit damage and ensure safe restart.