A condition where an engine receives an excessive amount of fuel relative to air is characterized by an imbalance that disrupts the combustion process. This over-fueling leads to incomplete burning of the mixture. For example, black smoke emanating from the exhaust pipe is a common visual indicator of this condition, stemming from unburnt fuel particles.
This state has significant implications for vehicle performance, fuel efficiency, and emissions control. Prolonged operation under these circumstances can lead to decreased power output, increased fuel consumption, and potential damage to catalytic converters. Historically, diagnosing and rectifying such issues were more complex, relying heavily on manual inspection and adjustments, but advancements in diagnostic tools have simplified the process.