A common issue with the USDM -GT-R is that the fuel line coating tends to come off over time. We've seen this not occur on cars for thousands of miles, or even our brand-new 2017 had the issue. This can occur regardless of whether not the car has had modified fuel lines or is running ethanol/gas, What essentially is happening is that the coating is coming free beyond where the fuel line is sealed. Gradually the fuel pressure pushes back and fills the lines coating causing it to leak fuel and swell. Eventually this can cause a pretty dangerous situation.

How do I know if I have the Problem?

The main indication of the line leaking is, well there's fuel coming out. In many cases the line coating will be bloated but upon closer inspection our untouched line was having the problem so make sure to check occasionally if your line has not been treated.

How to Fix the Issue

There are two methods available to fix the issue. The first is to simply install an all new hard-line. However since it's typically time and cost prohibitive to do so, the other option is to cut the line back.

If the coating is removed the hard-line can be more susceptible to corrosion so make sure to check occasionally particularly if you're running E85 as it can be much more corrosive to aluminum than traditional fuel.

Remove the quick connect fitting by allowing fuel pressure to go down then squeeze the tabs and pull upwards.
Using a sharp knife or razor-blade, CAREFULLY slice down along the liner starting at the top where it is already loose. Try to cut towards the liner rather than the line itself as scoring or cutting the line with your knife can cause it to leak and you'll be back at square one.
Now cut around the back side of the lip that sticks out then peel off the line covering.
Removing any more of the covering isn't necessary and just opens you up to the danger of more corrosion.
Since we were already there, we decided to go ahead and treat the other line as well. While this issue is more pronounced on the feed line, the return line can occasionally have the issue as well.
Before re-installing the lines lube them up well with something like Super Lube in order to allow the fitting to seal a little better, and it can prevent damage to the o-ring when installing the stock lines.
You're all done! Go out and enjoy!!