My has had a converter sitting in his basement for a few years. Was wondering if there was anyway it might have gone bad or is there a way to check to see if everything is still OK? Just trying to make sure everything is good before it goes into my car.

 

what brand is it? maybe you can call them and see what they say. they might want you to send it to them so they can check it over. as long as its not sitting wide open with no cap over it i would say it should be fine