Water/moisture getting inside my 4Runner...

[LBC99]

It was raining like crazy here in Southern California this past week and I noticed some water got inside of my 99 4Runner. All my windows and doors were closed properly.

The inside of the windshield and driver's side window were wet and fogged up. Also, I noticed the carpeting and floor mat in front of the passenger seat were wet, not to mentioned smelled pretty bad.

Is this normal? If not, what might be the problem? What can I do to fix it? This is the third time I have noticed that this has happened.

Any help would be greatly appreciated. Thanks.

 

[MicaBlue03]

One thing to check is the windshield seal. I haven't heard of any leaking from the factory, but the places that do windshield replacement sometimes mess up.

It's also worth checking the sunroof, but AFIK, that doesn't need to be a tight seal. Instead, the water that gets around the edge of the glass is caught in a tray under the glass perimeter, and drained out through tubes to the ground. I suppose it's possible that one of those drain tubes is clogged.

If you've been using the air conditioner a lot to defog the interior (the vehicle may have turned the A/C on automatically for you) and the A/C condenser drain is clogged, it may be possible for water to find another way out, into the cabin itself.

Lastly I can speak from personal experience on two vehicles (none Toyotas) that a leak in the heater core or associated piping can let the water/antifreeze mix leak into the cabin, causing the problems you describe. You may be able to diagnose this by identifying the bad smell.

Good luck; let us know what you find.

 

[LBC99]

One thing to check is the windshield seal. I haven't heard of any leaking from the factory, but the places that do windshield replacement sometimes mess up.

It's also worth checking the sunroof, but AFIK, that doesn't need to be a tight seal. Instead, the water that gets around the edge of the glass is caught in a tray under the glass perimeter, and drained out through tubes to the ground. I suppose it's possible that one of those drain tubes is clogged.

If you've been using the air conditioner a lot to defog the interior (the vehicle may have turned the A/C on automatically for you) and the A/C condenser drain is clogged, it may be possible for water to find another way out, into the cabin itself.

Lastly I can speak from personal experience on two vehicles (none Toyotas) that a leak in the heater core or associated piping can let the water/antifreeze mix leak into the cabin, causing the problems you describe. You may be able to diagnose this by identifying the bad smell.

Good luck; let us know what you find.

I've never had the windshield replaced, so don't know if it is that.

Someone on yotatech also suggested the heater core. How do I check that out or fix it? I'll describe the smell: It smells like someone has been smoking in my truck.

 

[MicaBlue03]

diagnosing heater core leakage

Leakage of coolant into the cabin could happen from a perforated heater core or from any of the pipes/hoses/valves on the driver's side of the firewall. I can think of several things you might do.

Check to see if you're losing coolant. Is the overflow reservoir low or empty? Open the radiator cap when the engine is cold and see if the radiator is full. Losing significant coolant might suggest that a leak is your problem.

Check to see if the wetness in your cabin (a wet carpet, say) has a funny feel to it. Coolant can make things the carpet (and your fingers) feel a bit sticky or oily.

The smell may also be a good clue. A carpet that's wet with water would normally smell musty. A smoky smell might indicate a coolant leak. Does the carpet smell like the inside of the radiator or coolant resorvoir?

The heater core and its piping are usually buried deep behind the dash, so these leaks can be a pain to diagnose and fix. Sometimes the leaks only happen when the heat is on or off, and that can be a useful clue.