For 1990-2009 cars

Service the air compressor air strainer filter, if equipped. Refer to Air Compressor Air Strainer Filter Replacement .

1. Check all of the air compressor bracket fasteners for looseness.
2. Tighten the air compressor bracket fasteners as needed. Refer to Fastener Tightening Specifications .
3. Check the following components for looseness and tighten as needed. Refer to Fastener Tightening Specifications .

• | The air compressor oil inlet hose

• | The air compressor oil outlet hose (LP4/L21)

• | The air compressor water inlet hose

• | The air compressor water outlet hose

• | The air compressor air inlet hose (LG5)

• | The air compressor discharge pipe

4. Check the air compressor discharge pipe for carbon restriction.
5. Clean or replace the air compressor discharge pipe as needed.
6. Check the governor cut-in and cut-out pressures.
7. Adjust the governor cut-in and cut-out pressures as needed. Refer to Air Compressor Governor Valve Adjustment .