ok, I just got an s4 t2 with 40,000 miles on a mazda rebuild. the car has some basic mods, and was boosting 11 psi. the first week i drove it the car ran fine but now the car wont boosted past past 5k. my first thought was the fuel cut defender had a bad connection but that wasnt it. I drove the car some more and found that under 1/2 throttel it would boost all the way to 7k but to the floor not past five. I have checked every vac hose I could find and there is not a leak. could it just be im not gettin the fuel I need?