Hi everyone. I hope you can help me with this one.
I have a 2002 Four Winns Vista with a 5.0 GXI-C dp. I just installed a Remanufactured long block. Has approx. 3 hours of run time on it. The motor will come out of the hole fairly well with a slight hesitation once in a while. I will just about get up on plane or just achieve plane and the motor starts to bog and drop rpm's. It then starts to backfire and pop if I keep the throttle wot. After I back it down it idles fine. It starts immediately and runs well up to about 25 to 3000 rpm.
Ok so what has been done and tested. It has a new set of plugs, wires are 2 yrs old and everyone has spark. New rotor and cap. I have removed the fuel pump assembly and completely gone thru it cleaning out all of the old paint and cleaning the screens in the pumps. I put it back together and also installed a new fuel regulator. The low pressure pump is at 14 psi and the high is at 51.
I have a new TP sensor as well as a IAC valve and new knock sensor.
I have tested the map sensor and it started at 4 vdc and went to 3.3 to 2.6 to 1.8 and 1.1 vac with every 5 inches of vacumn I put on the sensor during the test.
I have also made sure the entire intake manifold doesn't leak by running it and spraying starter fluid around every intake manifold gasket.
Also have a fresh tank of fuel in the boat. Also checked for codes and ecm has none.
I have a 2002 Four Winns Vista with a 5.0 GXI-C dp. I just installed a Remanufactured long block. Has approx. 3 hours of run time on it. The motor will come out of the hole fairly well with a slight hesitation once in a while. I will just about get up on plane or just achieve plane and the motor starts to bog and drop rpm's. It then starts to backfire and pop if I keep the throttle wot. After I back it down it idles fine. It starts immediately and runs well up to about 25 to 3000 rpm.
Ok so what has been done and tested. It has a new set of plugs, wires are 2 yrs old and everyone has spark. New rotor and cap. I have removed the fuel pump assembly and completely gone thru it cleaning out all of the old paint and cleaning the screens in the pumps. I put it back together and also installed a new fuel regulator. The low pressure pump is at 14 psi and the high is at 51.
I have a new TP sensor as well as a IAC valve and new knock sensor.
I have tested the map sensor and it started at 4 vdc and went to 3.3 to 2.6 to 1.8 and 1.1 vac with every 5 inches of vacumn I put on the sensor during the test.
I have also made sure the entire intake manifold doesn't leak by running it and spraying starter fluid around every intake manifold gasket.
Also have a fresh tank of fuel in the boat. Also checked for codes and ecm has none.
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