I have a 2006 F-150 Regular cab with A/C. It appears I also have a leak in the firewall or possibly in the plenum. Not sure which. The leak results in a puddle on the passanger side floor. About a cup in 24 hours whenever it rains, even when the truck has been parked. I can feel what appears to be a penetration stuffed with an open cell foam product. located on the firewall near the tunnel side. I can't tell if this is the source or if it's located higher up and running down as I can't get my hand higher.

Can someone enlighten me about this? Is it a common problem? Does anyone have experience with this type of problem. I bought the truck used w/o dealer warranty last month and this is the first rain I'd experienced. There is about 5 weeks of Mfgr warranty remaining. Would something like this be covered?

Thanks for any consideration you might lend to this question.

 

FWIW, I had 2 weeks left on warranty so I took the truck back to a Ford dealer and their 'rain doctor' found an unsealed joint in the plenum. They also cleaned out the A/C condensate drain tube. No more water on the floor.

 

Just had my 2005 fixed, the original condensation drain tube runs straight out the firewall. It will drain when the truck is sitting still, but when you drive, it forces the water back into the tube and it ends up draining out into the front passenger area. They replace it will an elbow and it fixes the problem. It should be a recall but haven't had any luck with that so far.