My neighbour has an 05 plate 3 door Astra and has found water trapped in the drivers side sill. It poured out when he removed the grommet. Anyone know how the water is getting into the sill? Not noticed any problem with my 08 plate 5 door.
If you mean the sill as in when you open the door, then this is a common problem courses by crap weather shielding and the bottom screws that connect the door card to the door, just put sealant in the holes and on the screw threads and around the speaker and you will be fine!