Turbo nytro cutting out at WOT...

[Nytroed]

So you all seem to know more about superchargers and fuel problems than me. I have a 2008 Yamaha nytro I have had for 3 years and haven't gotten it to run correct yet. SO here's my problem the sled had a 240 kit and was dead so installed a 180 kit had the clutch sent to Schmidt bros and awaiting to tune it until I can get the motor running right. It cuts out when pulling and the Afr runs lean when it cuts out. Would this be fuel pump failing? I'm stumped where to even start. I can turn the fuel controller all up and still lean. Mpi has been 0 help when I have contacted them.

 

[Turbo_everything]

Hey Nytroed, when it cuts out does it die or just falls on its face? At least you know your running lean, what Afr does it get to? In my opinion if it was a fuel pump it would be acting up at different times. A buddy of mines turbo 800 had pump issues and it would just die out of nowhere, you had to put a wrench in the tank and smack it a few time before it would work again. You could get a spare fuel line and "t" in a pressure gauge up to your bars to see if it's drops off, I run after market pumps at around 38psi but I'm not sure of the stock pressure. I would lean towards your tune or controller. Is there a boost reference going to your controller?

 

[Nytroed]

Hey Nytroed, when it cuts out does it die or just falls on its face? At least you know your running lean, what Afr does it get to? In my opinion if it was a fuel pump it would be acting up at different times. A buddy of mines turbo 800 had pump issues and it would just die out of nowhere, you had to put a wrench in the tank and smack it a few time before it would work again. You could get a spare fuel line and "t" in a pressure gauge up to your bars to see if it's drops off, I run after market pumps at around 38psi but I'm not sure of the stock pressure. I would lean towards your tune or controller. Is there a boost reference going to your controller?

It would do it every time going to wot. I figured out what I believe to be the issue. The person that had the sled before me didn't use submersible fuel line and there was a hole through the center of the hose instead of a 5/16 it was the size of a toothpick. The hose shrank down and starved the pump for fuel and that's what took the pump out. The pump I had was screeching and pumping air it seemed.

 

[Turbo_everything]

Wow that would have been awesome to find.... glad you found the issue. Have you run it after the fix?

 

[Nytroed]

Wow that would have been awesome to find.... glad you found the issue. Have you run it after the fix?

It's only been 2-3 years of searching lol and no I haven't yet I believe this weekend all the parts will be in for it. It should scream now!

 

[Nytroed]

Well the new fuel pump and filter is installed. I don't know what my Afr should be showing lifted off the ground. It kinda still has a stumble sometimes coming off of an idle. Could be old gas? Afr will only spike to 16-17 instead of 28 and up. But seems to bounce to 11 even. So I'm guessing that on the ground it should be going smoother and easier to watch. Also does anyone know where the hoses should be going like to the fuel pressure regulator and what is supposed to be to boost or vacuum? Possibly a schematic would be handy.

 

[Turbo_everything]

Well the new fuel pump and filter is installed. I don't know what my Afr should be showing lifted off the ground. It kinda still has a stumble sometimes coming off of an idle. Could be old gas? Afr will only spike to 16-17 instead of 28 and up. But seems to bounce to 11 even. So I'm guessing that on the ground it should be going smoother and easier to watch. Also does anyone know where the hoses should be going like to the fuel pressure regulator and what is supposed to be to boost or vacuum? Possibly a schematic would be handy.

That's too bad your still having issues. I feel your pain, i just now have mine where I want it. Mine will idle around 14 and if I hit the throttle it will drop it about 12.5 ish depending on amount. It sounds like a tuning issue, but hard to tell not seeing it. Maybe a dyno session will help you find the issue. Are you hooking up a rising rate fuel regulator? For vac lines I taped into the factory ones on the throttle body's and for my blow off valve I used the spare nipples on the throttle body's and t'ed them together just for the valve.