If water from the bulkhead area (or heater box drains, which in my case the heater box also contains the aircon cooling and thence condesation) gets under the box that holds the ECU it can pass from there through the large cable grommets above the footwell. We have this problem in hot weather when the aircon is on. I need to check the drain hose that I fitted and the neoprene gasket that I fitted to the flange of the ECU cover.

Peter

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