ok my alternator has been bitching around and working then not working then working all because of a plug...

i bent the connectors on the plug to make it tighter fitting then i took a tooth brush and cleaned off all the grease...

but why is there grease inside of it? whats it for? it seemed like the major cause of my alternator problem... after i cleaned it up the alternator is running like new and i never get that battery light again....

 

the grease helps keep water off the connection.

 

The other guy is right about grease does repel water, It also keeps it from corrrodeing. If you look at a new or rebuilt (alt) you will see a little dab of dielectric
grease on the plugs.