What is a common sign of injector wear in diesel engines?

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Rough idling or misfires are a common sign of injector wear in diesel engines because worn injectors can lead to an uneven fuel spray pattern or insufficient fuel delivery into the combustion chamber. This inconsistency results in incomplete combustion, causing the engine to run roughly or misfire, especially at idle when the engine operates at lower speeds and reduced power demand.

In contrast, increased fuel efficiency would generally indicate proper fuel atomization and combustion, suggesting that the injectors are functioning well rather than being worn. Quieter engine noise could imply a well-maintained engine, as noise can increase with injector wear due to inefficient combustion leading to increased vibrations. Lower exhaust temperatures are often the result of either an overly rich fuel mixture or poor fuel combustion, which is often tied to injector issues as well, but typically, a rough idle or misfires provide more immediate and noticeable symptoms of injector wear.