What is a common issue caused by improper fuel injection timing in a diesel engine?

Improper fuel injection timing in a diesel engine can significantly impact engine performance, and reduced engine efficiency is one of the primary consequences. When fuel is injected too early or too late in the combustion cycle, it can lead to incomplete combustion. This results in less energy being extracted from the fuel, causing the engine to use more fuel to achieve the same power output. Consequently, the overall efficiency of the engine decreases.

Additionally, improper timing can create higher levels of harmful emissions, contribute to rough engine operation, and can potentially cause other mechanical issues, but the most immediate effect observable is the reduction in efficiency, as the engine struggles to operate optimally under these conditions.