[north]

My experience is that often the problem is a mix of a bunch of things, like many people mentioned the repro upper seals on the actuators are junk, half the thickness of the originals. What helps is to rub axle grease on them and the shafts. It will help them seal tighter and prevents them from popping off.

The most common cause of the lights failing to close after shutdown (but working well during engine operation) is the checkvalve at the vacuum source near the carb being defective, installed backwards or missing in action.

When I buy a GTO with this system I usually spend a day tweaking the system starting at the carb and working down the whole system, hoses, fittings, switch, etc.

Often there are many small leaks; dried out or cracked hose at connections, rust holes in the can or the actuators, leaks inside the switch, cut or melted spots on the hoses, nonstock connections with other vacuum accessories like AC or cruise.

Alignment issues or drooping is often related to wear on the springs and the breakage of the main rod bushing, both tend to let the doors sag a bit when closed and parked.