The hideaway headlight doors wouldn't stay open. I installed a new vacuum hose kit and put new seals in both old actuators. Both doors held for a few days, but now the passenger side slowly closes after shutting off the engine. Drivers side works and holds like a champ. Bought a new actuator from Ames and installed it. Same thing, door slowly closes. Then i read that a weak spring could be the cause. Sent the actuator back, put the old actuator back on, ordered a spring and just put it on. Door slowly closes. Before anyone indicates it might be hose leak, i've taken two 3" pieces of hose and blocked them off with a screw, manually closed the headlight door, and put the hoses on the ports and let go of the door. Door still slowly closes. I blocked off the ports with the tips of my fingers, same problem. I don't know what the internals are in the actuator but if there is some kind of diaphragm that is there and is bad, blocking off both inlet and outlet should still hold a vacuum. Only thing left i guess is to re-order the actuator i sent back and see if with the new spring it fixes the issue. I suppose the new seal isn't sealing well enough, or like was said in an old thread, a pin hole in the actuator body. But again i want to reiterate, it did the same thing with a new actuator and the old spring. Has anyone had an unsolvable issue like this? Thanks for any and all input.