Water in left sill frame
 

I do not know the correct term in English, but my son's '07 STW had plenty of water inside the "sill frame". The splashing sound was very clear when braking and accelerating. Somehow the water has also flooded to the left floor, front and rear. The carpet and sound insulation were totally wet. Had to remove front seat and sill panels to get water out and heaters on duty.

Is it normal that rain water etc is guided to the sill frame? My ex-BMW E34 had a sunroof and water from there was guided into sill frame and further out. Does this car a similar system? However, my son's Mazda does not have any sunroof.

Maybe, I repeat, maybe the reason was in the front end of the sill. There are two rubber plugs. Huge amount of sand, mud etc was between the frame and the wheelwell protection plastic. I think the water may have been gone through plugs into sill frame because the mud prevented the water freely flooding to the ground.

Anyone had similar problems?