Hey, I have a new 08 F150 FX4 SuperCrew. Whenever the A/C is on, I hear a hissing or purging noise every twenty seconds or so on the passenger side of the cab. It isn't very loud, if I have the radio on and am driving I cannot hear it, but the passenger hears it. Anyone else have this noise?

If I turn off the A/C, it goes away. Recirc doesn't seem to affect it.

 

When I turn off my truck I have the exact same issue, but it's constant for about 20 seconds and then it stops purging. Sounds like the A/C, a little water leaks out onto the floor and then it's done. Anyone?

 

If what you're describing is what I think it is mine has done that since new.



Mine does that too, but no leaking on the floor.

 

Yup, I've got that noise too. Mines done it since day one and now 48K miles later still does. I wouldn't worry about it.

 

i took mine in when i got my truck 08 FX2 and the thing would do what you are describing after shutdown for a good 30 minutes. i took it into the dealership because i thought that it wasnt normal for it to be doing it that long. they did something to it and now its fixed. i think they said that they relocated the drain tube so that it doesnt leak out onto the exhaust.

 

they probably did the TSB about the PCV elbow on the drain tube exit to prevent drain back into the cab, and angled it so it would drip a little bit to the side from where it was.