In my W124, I have a water intrusion where the water collects in the passenger footwell. That foam stuff soaks it up...I replace with towels and bring it inside to dry...then put it back.

One of these days I'll have my auto body guy chase down the leak...but until then...

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 161k miles
06 E320 CDI "Rutherford", Black on Tan, 180k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 147k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 81k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife