Loss of RPM at WOT

[TownsendsFJR1300]

The high pressure pump INSIDE the VST has a filter at the bottom of it. It likes to clog up and hamper fuel delivery / pressure to the fuel rail- hence, running issues, especially at higher RPM's

Also check you Regular mailbox Ryan. That should help a bunch.

[crvbal49]

Okay guys, just wanted to update everyone in detail. From the beginning .... 2005 Yamaha F150 was running pretty smooth, but at wide open throttle It would only get to 5200 RPMs briefly, and then work its way down to 4400 RPMs and level out at about 33mph. I changed the spark plugs, which needed to be changed anyway, but no change. Then I took off the VST. It was nice and clean on the inside but I noticed the high pressure fuel pump filter inside the VST was holding gasoline . Since it shouldn't do that I changed that filter (and VST GASKET) and changed the injector filters at the same time. They also looked dirty. First open water test after that was a success. Problem is completely gone. 6000 RPMs at 46 mph.

I appreciate all the help guys. Thanks again.

[Jason2tpa]

Great news, congrats!

[TownsendsFJR1300]

Excellent, plus 1, congrates!!