What is the primary danger when an air compressor pumps oil into the pneumatic air brake system (compresor pasando aceite)?

1. The vehicle uses less diesel fuel
2. Oil sludge contaminates the air dryer desiccant cartridge, rots internal rubber valve diaphragms, gums up relay valves, and increases brake response lag or failure
3. The engine horsepower increases by 50%
4. The air tanks become magnetic