Possible leak, wet driver floorboard

[astrand1]

Ok guys looking for a favor. I have a leak that has developed in the last couple months. It’s in the driver footwell area. Seems to be coming from the floor up. I’ve checked some of the under carpet insulation and it’s wet on bottom but just a few inches going up the firewall it’s dry as a bone. I checked my sunroof drains and they are wide open with no leaks. Also checked the windshield with lots of water also dry. As I kept trying to investigate the source I noticed a small black grommet (pictured below) that had some witness marks of a little bit of water and small amour of road dirt that matches what’s on the body directly below this grommet. I got under truck and I’ve circled the larger rectangle hole that’s just above the step motor. What my favor I’m asking is could a couple guys maybe with a newer truck (mine is 23 lariat) and or same year if possible look under there and take a pic of the hole I have circled to see if there is supposed to be a grommet or seal on that large rectangle hole or not. After thinking back the truck sat here in LA over Xmas and there was torrential rain for days and this area was by all accounts pretty dry. But I drove the truck on the last day of rain on Sunday and I really think this hole that is right behind the driver front tire is allowing water to spray in while on highway and it’s coming up thru the black round grommet. I’m going to seal it with some silicone but I’d like to cover that other hole if it is supposed to have one. Had my truck for over a year and had always been dry so something changed. Thanks.

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[Maquis]

That hole is open on my 23. I don’t have power running boards.

 

[astrand1]

That hole is open on my 23. I don’t have power running boards.

Thank you for the quick response. Easier to take pic without the power boards. lol. I’m kinda thinking it’s supposed to be open but the round grommet was kinda loose in the hole. So I think that might be the offender.

 

[chriserx]

Might help to know if the smell in the cab is neutral (water), moldy (stale water) or sweet (coolant)

 

[astrand1]

Might help to know if the smell in the cab is neutral (water), moldy (stale water) or sweet (coolant)

Moldy, ass smell. Definitely been there for a min.

 

[chriserx]

Hmmmm...Michigan temps and the rain was 5 days ago, unless you're keeping the truck in a warm ass garage, I'm inclined to say that's not likely the source, sunroof perhaps?

 

[astrand1]

Hmmmm...Michigan temps and the rain was 5 days ago, unless you're keeping the truck in a warm ass garage, I'm inclined to say that's not likely the source, sunroof perhaps?

Must be TLDR. lol. Truck and I are in LA. And already checked sunroof. That was the first thing checked.

 

[chriserx]

Must be TLDR. lol. Truck and I are in LA. And already checked sunroof. That was the first thing checked.

My bad, went with your profile location and figured it was a xmas vacation trip. Still think that hole is fairly unlikely, unless you were fording water and not splashing puddles that is. Check your windshield, someone in the last couple weeks posted about their windshield leaking iirc.

 

[astrand1]

My bad, went with your profile location and figured it was a xmas vacation trip. Still think that hole is fairly unlikely, unless you were fording water and not splashing puddles that is. Check your windshield, someone in the last couple weeks posted about their windshield leaking iirc.

I did check the windshield. Used lots of water. The reason I suspect that hole is because the only areas wet are the bottom and the wettest area almost directly above that hole. Anything going up firewall and the piller are completely dry. Plus the witness marks in, under and around that grommet. It’s just very suspect. So right now I’m drying out the carpet and Lysol-ing it to try and knock down the smell somewhat. Then going to silicone the grommet and just have to wait until the next big rain and see. I’m leaving the trim at base of a piller off as well as the little kick plate area so that I can easily pull up the carpet and keep an eye on it. Again it’s a hunch but seems like clues are pointing to it.

 

[chriserx]

You can try putting some talc powder down to help isolate the source, where the talc runs would give away where the water source was.

 

[chl]

F-150's have for a long time, and the Lightning is no exception, had water leak issues.

Water building up inside the doors and rocker panels, gets in from the windows apparently, and can get into the cabin from there.



The moon/sun roof is another common leak spot.



Also behind the rear seat there is a vent of some sort on F-150s that opens towards the bed, I think thee was a forum post about that one.



If you look at YouTube you'll find a plethora of ways water can get in:

https://www.youtube.com/results?search_query=f-150+lightning+water+leaks

Any water getting in will find the lowest point and collect there of course.

 

[chl]

Actually, I saw the rear vent leak post on another f-150 forum site - not able to post the lnk here as a result.

 

[astrand1]

F-150's have for a long time, and the Lightning is no exception, had water leak issues.

Water building up inside the doors and rocker panels, gets in from the windows apparently, and can get into the cabin from there.



The moon/sun roof is another common leak spot.



Also behind the rear seat there is a vent of some sort that opens towards the bed, I think thee was a forum post about that one.

If you look at YouTube you'll find a plethora of ways water can get in:

https://www.youtube.com/results?search_query=f-150+lightning+water+leaks

Any water getting in will find the lowest point and collect there of course.

Appreciate the links. Good for me and others who have had or having issues. I’ve seen that first video before. I am lucky that while I’m at work some days I’m kind of on standby and that gives me hours of time to get into this. I spent the better part of last week working on this problem. I started with the sun roof. The drains are clean and open and no leaks from the drain hoses that we have been able to see. Put gallons down those. Then worked on the windshield. Many many gallons there with no obvious intrusion. I moved to the rear checked the glass, also the 3rd brake light and vent and then carpet as well. Everything was bone dry. The doors I suppose could be possible but we saw no signs of any water and all drains are open free and clear of anything. I’ve had the truck since new bought in Aug of 24. It’s been across the country 3 times so far and when home in Michigan always in a garage or my shop. Out here in California it does have to sit outside unfortunately. But all the rain that we have gotten I’ve had no issues. And it’s not super wet like pooling. The wettest area was concentrated to the area pretty much right above that black grommet. The padding was pretty wet and then just the very bottom of that padding that goes up the firewall right above the dead pedal. But only the bottom and it was not as wet. There were witness marks around that grommet that sure seemed suspect. And after the huge amount of rain that the truck sat in over Xmas (I think records were broken) it was not very wet. Except for that Sunday jam 4th it rained very hard all day and I was on highway driving most of the day so water would have been just spraying up from the driver wheel right into that bigger hole and into the cavity where the grommet is. It’s almost directly above that bigger hole. Anyway sorry so long. I’m thinking out loud. Retracing steps. So I’ve now siliconed that grommet in and have been drying out the padding. What a bitch that is! Such a small area but it takes forever with a fan and heat blowing on it. Also used my small ozone generator under there and that has helped a lot with the ass smell. I leave the truck open doors etc and put the ozone gen. Under the propped up carpet with a furniture pad over the area to concentrate the ozone just to that area. I’ve done a couple 20-30 min treatments. Now I’m leaving the sill trim and bottom piller trim piece off so I can access the carpet area easy. Will be going thru a car wash tomorrow and then just have to wait for the next rain and driving to see if there is any more intrusion.

 

[chl]

Appreciate the links. Good for me and others who have had or having issues. I’ve seen that first video before. I am lucky that while I’m at work some days I’m kind of on standby and that gives me hours of time to get into this. I spent the better part of last week working on this problem. I started with the sun roof. The drains are clean and open and no leaks from the drain hoses that we have been able to see. Put gallons down those. Then worked on the windshield. Many many gallons there with no obvious intrusion. I moved to the rear checked the glass, also the 3rd brake light and vent and then carpet as well. Everything was bone dry. The doors I suppose could be possible but we saw no signs of any water and all drains are open free and clear of anything. I’ve had the truck since new bought in Aug of 24. It’s been across the country 3 times so far and when home in Michigan always in a garage or my shop. Out here in California it does have to sit outside unfortunately. But all the rain that we have gotten I’ve had no issues. And it’s not super wet like pooling. The wettest area was concentrated to the area pretty much right above that black grommet. The padding was pretty wet and then just the very bottom of that padding that goes up the firewall right above the dead pedal. But only the bottom and it was not as wet. There were witness marks around that grommet that sure seemed suspect. And after the huge amount of rain that the truck sat in over Xmas (I think records were broken) it was not very wet. Except for that Sunday jam 4th it rained very hard all day and I was on highway driving most of the day so water would have been just spraying up from the driver wheel right into that bigger hole and into the cavity where the grommet is. It’s almost directly above that bigger hole. Anyway sorry so long. I’m thinking out loud. Retracing steps. So I’ve now siliconed that grommet in and have been drying out the padding. What a bitch that is! Such a small area but it takes forever with a fan and heat blowing on it. Also used my small ozone generator under there and that has helped a lot with the ass smell. I leave the truck open doors etc and put the ozone gen. Under the propped up carpet with a furniture pad over the area to concentrate the ozone just to that area. I’ve done a couple 20-30 min treatments. Now I’m leaving the sill trim and bottom piller trim piece off so I can access the carpet area easy. Will be going thru a car wash tomorrow and then just have to wait for the next rain and driving to see if there is any more intrusion.

You'll have to make a video about how you fixed yet another leak point if that works!

I could see how driving through deep water could cause it to get up there through the bottom.
There are so many open spaces under the truck, it's ridiculous!
Animals have been known to crawl up there to take shelter and chew on wires!

Hope that fixes it, keep us posted!

 

[bc1]

You also have to watch out for blowing dirt and dust coming up the fender wells in and around the frunk area where your battery and heat pump is. Might have to blow the dust out with an air compressor if you are in those conditions.

But then your main worries are a fire, a mud slide, and of course, California falling off into the ocean any day, hour, minute, or second now.

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