We have a 2006 Ranger 500EFI, it will start and idle okay, when the throttle is opened the engine boggs like it is not getting fuel. Yes the air cleaner is clean, battery posts are clean and tight, no it hasn't been sitting with out being used, it gets used daily to haul feed. Problem has been developing for about a month but had been running well enough to use. We installed a pressure gauge hooked up we have 39-40 psi @ idle, moving @ full throttle psi drops to 25-25 psi, no problem, took the gauge off and problem came back. This has happened twice, once we could get about 1/2 throttle, once no throttle, put the gauge back on, response is back. We had to use an inporvised connection for the gauge as the schreader valve test port that is supposed to br there is not on this unit. Any thoughts on it? Any information for after market fuel pump as the OEM calls for a fuel tank/pump assembly. Pump in tank is a Bosch # F01RBOS055, however that number doesn't come up anywhere we can find yet.

Thank for any help.

Northern Nevada Pullerguy