After a week of being parked up over christmas, I gave my Galant a once-over before returning to work tomorrow. The front passenger footwell was damp with water.

I removed the glovebox, I can see water dropping from the join between the black AC unit and the white vent fan unit. I removed the cabin filter, it was damp. I stuck my phone in to record a video of the fan itself, there is some water sat in the housing that is presumably working its way out through the module joint.

The sponge gasket between the top of the vent fan unit and the shell is soaking as well, so I am fairly confident the water is coming in through the vent unit fresh air intake.

Does anyone know where said air intake hole is and how to get to it from 'outside'?

I also checked under the bonnet, there is a copex shrouded wiring loom that passes through the bulkhead, the rubber grommet had a small hole in it so I daubed some sealant in case that was the problem. I also cleaned some crud away behind that loom and under the wiper motor.

Next step is to pop off the plastic scuttle panel when the weather is better, and check in there for any blockages.