I have a 2000 F150 XL with the 4.6L Triton V-8 engine. I am having a problem with moisture. Everytime it rains or I wash the car it won't run. It starts everytime, but will not run. At first I did not make the connection with the moisture thing and I took it to the dealership and they said it was the fuel pump and replaced it. It kept happening so I took it back again and they said it was the master air flow sensor and replaced that. Still kept happening so I took it to an independet mechanic and he could not find anything wrong. Not until I made the connection did it start to make sense. Everytime this happened I would have it towed to the dealer but by the time it got there it had already dried out and therefore they could not find anything and it would run fine. So I don't know what to do. Any clues? Any ideas on what is getting wet and causing this? Like I said, it starts everytime and will idle momentarily, but then stalls. It even happens as I am driving and has happened in the middle of intersections and busy streets. Very annoying!!! Please help!!!

 

Hi and welcome to FTE

Check under the dash area. Sometimes if the windshield leaks, it will get into the electronic boxes and shorts them out.
Jimmy

 

Thanks for the welcome! I looked under the dash and there is some rust. Is that normal? Or is that a sure sign that it is getting wet?

 

I would run the hose over the windshield for awhile, then poke around down there and see if you see any water. If so, then I would go to a good glass shop and have the windshield resealed.
Jimmy

 

Hey, good idea. Tonight I went out and turned the truck on and let the hose run over the winshield. After about 2 minutes it died on me as usual. Right after I looked under the dash but did not see any water. However, I am convinced that it is seeping in through the winshield somwhere. Tomorrow morning I am going to a mechanic to reproduce the problem for him and see if he can find anything. I will let you know. Any ballpark figure on how much it cost to reseal the winshield and where I would do something like that?

 

Most insurance companies will replace your windshield for free if it is damaged......Might be worth checking into in case it happens to "recieve" some "damage" for some reason......

 

Well, I have checked for moisture under the dash after spraying the car with water and had a mechanic neighbor come over this morning to help out, we found nothing. We opened the hood and sprayed the engine lightly and got the car to die. He could not find anything wrong. So the problem continues. We did conclude thought that the water is not seeping through the windshield, so it should not be that. Not sure where to do from here...

 

mcb45,

When it runs and dies do you get a CEL? Have you checked for DTC's? Maybe whatever is shorting out is setting a code. Let us know. Maybe someone can help.

Bill

 

By the time that I get the truck to the mechanic whatever is shorting out is dry and therefore they are not pulling any codes. I am going to take it down there and hose it down in front of them and make it die and see if it outputs any codes, but up tp this point nothing...

 

Well, I took the truck to the dealership and they told me that my #1 and #3 cylinders are full of water and the coils are ruptured, the MAF sensor is bad and a few other things. Has anyone ever heard of the cylinders filling with water? Any clues?

 

Did you spray the engine down? Drive thru a river?
If not, the Hood may not be sealing right allowing water to get onto the engine. When it gets into the plug pockets, it usually cooks the coils due to it sparking straight to ground.
If #1 got water in it, then I would say that it has been hosed off or something.
Jimmy

 

I detailed the engine, and did use a pressure sprayer. I have always done that with all my cars though and had never had any problems. Could that really happen?

 

If the cylinder has water in it, so will your oil.

 

Will the car still run with water in the cylinders?

 

Hi, I got a 2000 F-150 w/ a 4.6L and I went on a longer trip down south about 1000 mile one way trip for a nascar race and got behind a semi in the rain where it was very misty. And my truck started to buck and miss like the the tranny was going. But later that day when it got warmer and dry out it ran fine. But after and over time the check engine light came on for #1 cylender miss Ihad it checked at a parts store. I then got it back home to a ford dealer and they found abad plug, it had small hair line fractures in it so when it got wet it would miss fire. And ford also said that your truck has to go through a # of many cycles of miss firing to have the check engine light come on so you could have some bad plugs. So good luck!