2003 RLXI 335 monsoon idle issue Please Help!

[BarOne]

Ok need serious help here... first I'll include what I've done thus far, dist cap, rotor, wires, plugs, IAC, TPS and finally fuel pump.

Issue... Discovered while trying to figure this ghost out, when I connect the gas inlet side of fuel pump it stutters and stalls. as soon as I pull it off it smooths out and idles fine. Ruled out any fuel tank restriction by using a clear tube stuck into a 5 gallon gas can. Stick the end of the tube into the gas, stutters and stalls, pull it out and she smooths out and idles fine till it finally runs out of fuel.

Let me add I put a volt meter on the pump when tube is in the can and sucking...getting 13 volts. So I assume voltage is not the issue.

Could pressure regulator be causing this?

Boat going to dealer later to search for possible codes, I'm at a loss.

[Cap305]

Is there possibly a restriction in the fuel return line? Just a wild arse guess. You can test the fuel pressure regulator by putting on a fuel pressure gauge on the test port then start the engine. You then disconnect the vacuum line and see if the pressure spikes up. If it does the regulator is probably fine.

The link is for testing automotive fuel pressure regulators but it's the same theory.

One question though, is this happening at start up or is this happening after engine is in the process of warming up? Just curious.

[BarOne]

Thanks for the suggestion Cap, didn't think of testing return line. I'll add that to our next move. Gotta admit... it's a weird one.

Start up and after warm up.... if I can get it to run long enough, it runs at 150 -160 degrees.

Edited July 24, 2015 by BarOne

[BarOne]

Diagnosis from marina is is fuel pressure regulator, part arriving this Friday. Any ideas what this should cost for the part?...I hate getting raped for something I should have done myself!

[BarOne]

Fixed... Fuel Pressure regulator. Although I got stroked on part $$$ we're back on the water!