Corolla Sport Coupe L4-1587cc 1.6L DOHC (4A-F) (1988)
Expansion Valve: Testing and Inspection
Removed
Expansion valve test
1.
Connect manifold gauge set to expansion valve and refrigerant container, Fig. 14.
2.
Close both gauge hand valves.
3.
Pierce refrigerant container to release pressure.
4.
Open high pressure hand valve and adjust high side pressure to 70 psi.
5.
Dip remote bulb of expansion valve in pan of water. While varying the temperature of the water, read low pressure gauge and at the same time
measure temperature of the water with a thermometer.
Expansion valve pressure/temperature graph
6.
Compare the two readings on chart, Fig. 15.
7.
If crossing point of readings do not fall within the lines, replace the expansion valve.