OK, son managed to drive through flood water on Friday and I’m guessing it’s done something but I’m not a mechanic, it’ll be in the garage Monday but just wondering if anyone has an informed view on problem.

Car is a 2010 1.2 Vauxhall Corsa petrol

It went through the flood 12-18” water on Friday morning.
Friday night a warning light came on (Yellow car with spanner) that indicates “engine/transmission, electrics” warning (which seems to cover everything but zombies)

Car still drives but loses power on hills and has very little when pulling away.

I’ve had done following.
Lifted bonnet and had a listen to engine at idle - all sounded good no misfire or odd out of sync sound. (Lol)
Took air filter out, it was bone dry.

From my very limited and not a clue knowledge I have decided it’s water in electrics somewhere, if I leave it will it just dry out on its own?

Or will leaving it cause more damage?

As I say, it’ll go to garage Monday but as will all things I keep trying to fix it in my mind now.

Any thoughts anyone?