Hey guys. Just rebuilt my powerhead on my 1994 Mariner 175 EFI 2.5l and took it on its maiden voyage tonight. I pulled out of the no wake, came up on plane and noticed the engine didn't seem to be hitting on all cylinders, so I idled down and was listening to the engine. Tried to get back on plane and the motor wouldn't do it. I changed my plugs all out on the water thinking they could have fouled from running in the driveway on my rich mixed gas, didn't fix the problem. The engine would idle fine and rev through the rpm range in neutral. So I decided to idle back to the dock and load it up. Came home and checked the fuel pressure and it is 45 psi engine off. I have also noticed at times my fuel pump will not prime or cycle, and when this happens the engine will not start due to fuel pressure. According to my manual, power and ground is supplied directly from the ecu. Anyway guys, im looking for any insight I can get. Things that I have tried are spark plugs, fuel pressure test/engine off, examined all engine grounds, fuel filter installed between tank and engine, replaced fuel water separator, new primer bulb, and the gas tank is properly venting. Also all of the fuel injectors were sent out, tested, and cleaned during rebuild. Thanks in advance, Brad.
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