plugged evaporator drain tube or the heater core has gone bad
water in passenger floorboard, where is the hose that would cause this?
A damaged heater core will cause coolant or water to leak onto the passenger floorboard.
If that water is engine coolant, the heater core is leaking.
This would be caused by a leaking heater core, or a leak in the plumbing associated with it.
HEARTER CORE STARTING TO LEAK .PASSENGER SIDE FLOORBOARD UPPER TOP CORNER. LEAK WILL START TO GET CARPET WET AND WINDOWS FOGGED UP.
A water leak from the radiator in to the passenger compartment is usually a sign of a leak in the heater core. If the water is not from the radiator then there may be a leak in a window or door seal, or a hole in the undercarriage that is allowing water from the road to soak the carpet..
I have a 98 neon .it had the same problem. take your tail lights out and put a thick bead of silicone where that gasket is between the body and the tailight and it should solve your problem. remove the gasket
Have you used your air conditioning lately? The most common reason for water to appear to be leaking on the passenger floorboard is that the condensation drain for the air conditioning is plugged. Unfortunately, the drain is pretty much inaccessible to the average person and I have yet to discover a reasonable method of clearing it other than paying the dealer or a mechanic to do it. The other, less common causes for that type of leak is that the heater core is leaking, in which case the fluid will be antifreeze rather than water, or the door seal on the passenger door may be leaking, or the windshield gasket may be leaking.
Check the door seal under the door, it may be bad.
Either your windshield or driver's side window has a major leak
Look for the tube that takes the condensed water out of the cabin these sometimes get knocked loose by the feet of the passenger's
Windshield seal? Heater core? Evaporator drain?