Hello all.. I hear a loud hissing sound coming from the center vents in the car when the ac is on. Could this just be the sound of the Freon working it's way through the system, or one of the vacuum pods leaking. Has anyone had this problem or heard this sound, coming from the vents.. I am a little low #7 is at 6bars I know I need some more freon.. Has anyone added oil NOT from Mercedes How much did you add?

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Peter L. House
1998 Sport E430
Azure Blue
110,000k Miles

1987 Oldsmobile Cutlass Salon
V8 Bucket Seats
Factory Moon Roof