I have a very slow leak in the freon and nobody can find it they put dye in several times and charge it. It lasts a year and then needs to be charged again. They use a sniffer at the vents.

Anyone have any ideas?

 

Is there a weak spot in the A/C system that normally goes bad?

 

Well there are numerous spots in the a/c system that can go bad. All the areas where there are seals connecting the lines together. Bring it to another shop and then see if they can find it and maybe the other shop didn't look throughly enough. Another thing to do is on a humid day run the a/c and if you still have the dye in it check the water coming out from the bottom. If the evaporator is leaking the water should glow under the UV light. Did they check the car after a week of running the a/c ? Cause they should have found soemthing then.

 

I have the same exact problem with my sc400. Blows ice cold a/c for about a year and one day gone.

 

I also forgot to mention the filler vavle cores on the high and low pressure side lines. Common place to leak especially if you don't have a cap on it.

 

Thanks. they have checked the evp coil water no luck. They also checked a week after the dye again no luck. I will try again this summer.