For 1990-2009 cars

Problem | Action
--- | ---
The piston rings are worn out. | Overhaul or replace the air compressor.
The engine air filter is dirty. | Replace the engine air filter.
The inlet vacuum is high. | Clean or repair as needed.
The air compressor oil outlet hose is restricted. | Remove the restriction or replace the air compressor oil outlet hose.
The engine oil pressure is too high. |

1. Determine the cause of the condition.
2. Repair or replace as needed.

The air compressor oil inlet hose is flooded with water. |

1. Determine the cause of the condition.
2. Repair or replace as needed.

The air compressor oil outlet hose is flooded with water, gasoline engine. |

1. Determine the cause of the condition.
2. Repair or replace as needed.

The air compressor oil outlet return passage is flooded with water, diesel engine. |

1. Determine the cause of the condition.
2. Repair or replace as needed.

The piston rings are not properly seated. | Overhaul or replace the air compressor.
The back pressure exists from the engine crankcase. | Determine the cause of the back pressure and repair.