Protege L4-1839cc 1.8L DOHC (1990)
^ Extremely High Head Pressure
^ Overcharged A/C System
^ Plugged Receiver Drier
^ Malfunctioning Expansion Valve
Perform steps 1 and 2 below prior to replacing any A/C related parts.
1. Install a manifold gauge according to the workshop manual and perform a performance test.
2. Record high and low side readings and compare to tables in workshop manual.
^ If discrepancies are found, repair as needed.
REPAIR PROCEDURES FOR COMPRESSOR NOISE
1. Apply the parking brake and start the vehicle.
2. Run the engine at a constant 3,000 - 4,000 rpm and switch the A/C system ON and OFF intermittently.
^ If the noise is still present, turn the A/C off for approximately 1 - 2 minutes and repeat the process.
NOTE: This process it designed to free a possible sticking compressor "vane."
^ If the noise is still present, proceed to step 3.
3. Evacuate the system.
4. Charge the system (with the correct freon) through the high side.
NOTE: This process is designed to free a possible sticking compressor "reed" valve.
5. while charging the system, add an additional 40cc of the designated compressor oil (Mineral Oil for R-12 systems, PAG oil for R-134a systems).
^ If the noise is still present, replace the compressor.
WARRANTY INFORMATION
After removal, install shipping caps to prevent refrigerant oil spillage and contamination. Insert the compressor into the container used for shipping and
store the part for future inspection.
