Brand x

I've got about 10 mpg ever since I bought my 86 4runner. However, after I bought it, I noticed there was no vaccum line connected to the bottom of the fuel pressure regulator and it was leaking gas. I know it is supposed to return the excess fuel to the tank but there is no where to connect a line going to the tank. So, I spliced a 3 way into the return fuel line and connected the regulator line to that, but...I'm still getting the same bad gas mileage as always but without the fuel leak. Any suggestions/info on where the regulator vaccum line is supposed to go or why I'm getting such bad gas mileage?