To remove the solenoid you have to disco the linkage. To disco the linkage you have to mark the position of the trunk latch and then remove the bolts from the latch so it can move around. Then you can work the linkage off. The solenoid can be dissembled and cleaned. You will see the brass lands that control the motor function. Clean them, check for burrs and high spots on the lands,contacts and plastic guides. Lube the lands and contacts with dielectric grease only.
jeff