How does a diesel engine's performance typically change at higher altitudes?

At higher altitudes, the performance of a diesel engine typically decreases due to reduced air density. As altitude increases, the air becomes thinner, meaning there are fewer oxygen molecules available for combustion. Diesel engines rely on a precise mixture of air and fuel to operate efficiently, and the reduction in available oxygen can lead to less efficient combustion.

This lowered air pressure affects the engine's ability to draw in enough air for the necessary fuel combustion, ultimately resulting in a reduction in power output. In essence, because diesel engines operate on the principles of compression ignition, the efficiency with which they can perform is directly impacted by the oxygen availability, which diminishes at higher elevations. Consequently, it's crucial for operators to be aware of this performance decrease and potentially make adjustments to optimize engine efficiency in high-altitude conditions.