The easiest way to check and see if the fuel pump is on its way out and no longer can build up enough high pressure (yes the Walbro's tend to do this occasionally) is simply to screw in the fuel pressure tester into the fuel rail and take a pair of pliers and pinch the ruturn line for a second. The dial should instantly go beyond 100 psi for that moment. If it hovers somewhere around 80-90psi, its on its way out. Oddly, it still is usable for people running 60psi setups with no problems. Strange. I believe someone once said that it's the regulator valve? in the pump that prematurely weakens and cant handle the high pressures.....dont quote me on that though.