smj999smj· Premium Member
It would help if we had a model year.. As far as dye, Nissan started putting green dye in their A/C systems at the factory somewhere around the 2000 model year or so. If the hose is not damaged or leaking, there is no reason to replace it; you can just replace the "O" ring. It's not what I would consider a common thing, but, perhaps, when they replaced the compressor, they did not tighten the bolt on the hose enough? Most auto parts stores carry "O" rings; just have to match it up and lube with A/C oil before you install. Whether you get a vacuum pump and do it yourself or let a shop do it, is up to you, but, if it were me, I would want to see what high and low side pressures are after recharging to make sure they are in proper range.