LINER 1091993 - Caterpillar

Adjustment of the fuel system outside Caterpillar specified limits will not improve fuel efficiency and could result in damage to the engine.
If you feel you have a locomotive performance problem, first consider the impact of locomotive efficiency and operating characteristics (speed, design, etc.), on power demand before questioning engine performance.In the case of poor fuel economy, the engine is not likely to be the cause without the presence of excessive exhaust smoke and/or a significant loss of power.If you feel you have a valid engine performance problem, contact an authorized Caterpillar dealer for assistance. If your engine is under warranty, then the Caterpillar warranty or extended service coverage (if purchased) will cover the cost of resolving a valid engine performance deficiency. However, if the engine is not found at fault, all costs incurred will be the responsibility of the owner. Refer to the Warranty and/or your Caterpillar dealer for details.