This is from the seal around the vent on the outside portion of the panel. Check the seal and use some silicon to fix it up.
Probably water getting in the distributor cap.
Check AC drain and clear the blockage. Also look for firewall sealer skips.
Since it happens only when it rains, it would suggest a few possibilities. Look for these:Bad window or door seals.Bad windshield seal.Holes in the floorboard or firewall, especially near the wheelwells.
water in distributor cap
No
the air conditioning pump is on the passenger side thats the only thing that leaks water there
Water getting into the door and getting the wires wet.
heater core is leaking.
yes
To replace the water pump in my 2001 Dodge Ram 1500 v8, it was $375 including labor and everything.
There is obviously a leak in either the firewall/cowl area or the window seal.
Because the air conditioner is running.