I’ve got a 2005 f150stx 4.6 300k miles and I’ve have a problem with the ac for a while bought it from a buddy about a year ago for cheap he had it drove it with ac then sat for about 6 months till I bought it now the ac doesn’t work used dye found one leak and fixed it thinking it was the only one I replaced the high and low pressure lines because there one price on these trucks fill it up with Freon and leaked out fast used more dye can’t find any dye please help

 

Don't know to just what extent you went installing the dye. If the system was completely empty ,you should have used a vacuum pump to assure there were no other leaks.
In your checking procedure did you look at the evaporator inside the vehicle? Taking short cuts as done so far, will not reveal the leaks and if you don't have the equip and background, you could be shoveling out a lot of unnecessary $$. .

 

what’s a way to check the evaporator without tearing the whole dash apart don’t really wanna do that just yet if I’m not certainnn be it’s it but I also read up on the drain tube for the evaporator and seems to see white water lines and greenish dye could be a coolant leak cause I do leak a little coolant very slow but I don’t know if that Freon could cause something like those water streaks cause it’s all over the place below the drain tube and on **** underneath the truck

 

One way to check the evaporator is with a sniffer,leak detector, that will confirm if refrigerant is leaking out there.

You also could try a cooling system pressure tester to see if the cooling system has a leak, which is a simple way to possibly explain if what you are seeing is coolant or dye.

 

I’ll have to rent a tool this weekend and see about that vacuum tool but how will that tell me where it is cause when I fill my system it leaks out in the matter of 30 min and it never really gets cold and the vacuum doesn’t tell you where you have a leak it just lets you know you have a leak if I’m not mistaken

 

I would say your reasoning is correct.

Since you already know there is a leak, you would need to add refrigerant and hope to pin down the area either with a soap solution or a sniffer which is a lot neater.

This is where having the right equip is important. Even if you feel you have corrected the leak,you still need to evacuate any air,which contains moisture,from the system and this also helps verify there are no other leaks. Sooner or later we come across a high pressure leak that only shows up when the system is operating.

 

I’ll look at getting a sniffer I’ve been looking into that and I’m not sure if I mentioned it or not but when I add Freon to the system fully charged up and all it makes a hissing noise even when I turn it off and yes I know that the pressures equalize but it keeps hissing for a long time then there’s no Freon in it wondering if that could maybe help narrow it down and could a compressor leak but not show any leak of dye