Recent content by Markdelz76

  1. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Good insight I’ll check it out. External gas tank was hooked up so bypassed a lot of those fuel lines. I also did injectors but will check the connectors. Thanks!
  2. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    We hooked up a fuel pressure gauge at the rail when it was sputtering and it was dropping pressure therefore assumed it was the HPFP. The LPFP was also leaking gas into the oil, so I do believe it is a combo issue here. My thermostat was definitely bad as well. I am going to look into another...
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    Yamaha 115 4 stroke sputter/stalling. Help!

    Got a certified Yamaha mechanic and still stumped. So far replaced low pressure fuel pump, high pressure fuel pump with VST, thermostat, VST and ran off an external tank. It runs better than when I originally posted this, but it still sputters (doesn’t stall anymore). Waiting for the mechanic to...
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    Yamaha 115 4 stroke sputter/stalling. Help!

    I saw this on a post - Here was Rodbolts advice on that thread... here's what creates the 700 RPM or so idle. mostly its by the temp sensor, TPS and ISC. its possible the t-stat is stuck its possible the ISC is sticking or dirty and its possible the TPS voltage is incorrect. the ECU will...
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    Yamaha 115 4 stroke sputter/stalling. Help!

    I wish I could use a diagnostic terminal but it’s a 2000 so I can’t hook a computer up to it. Ran for 10min at idle speed. I can start it back up then it dies faster. I am going to replace the thermostat and see what happens. If that isnt it, I may need to hire a mechanic. Not sure what else it...
  6. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Well, replaced the IAC and it ran fine for 10 minutes on the muffs and then died out. The IAC is pretty hot to the touch. Any other ideas?
  7. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Thanks for your help man! I ordered a new IAC and will update after that. I also will check the oil for any gas in it. My fuel pressure regulator is pretty rusty too, so thinking I am going to replace that as well
  8. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    The motor shudders and stalls when it is in idle position. When it acts up, moving the throttle does not fix it. But last time it was in the water, I plowed back to the marina around 2-2500 rpm And it did not stall or shudder. It was only a quick ride though, about 2 football fields. Right when...
  9. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Ok so update. Replaced injectors and spark plugs. Put fuel pressure gauges on fuel rail and read 37 psi when running. Put fuel pressure gauge after low pressure fuel pump and read 10-11 psi when running. It is still stalling. Right before it stalls the gauges stay about the same, maybe go down a...
  10. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Yeah I changed them last year. Going to pull these today too
  11. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Yep, above 2k and yep above 2k all was ok. Once I pulled back, it sputtered and then stalled. I am definitely checking fuel pressure at fuel rail and after low pressure pump
  12. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Yeah I tried pumping bulb when it was sputtering/before it died and nothing changed. Starting to wonder if it’s my idle air control valve. Going to the marina today to take a look
  13. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    No fuel additives. Ethanol free. Water separator changed and fuel filters. If water was in gas wouldn’t it run like crap all the time? Not just below 2k rpm?
  14. M

    Yamaha 115 4 stroke sputter/stalling. Help!

    Yep printer bulb is firm and did not help the issue when it was bogging down. I replaced plugs last year but will check them for sure. I did replace the coil packs 200 hours ago so they are new. The filters are all full. I start with plugs and then test pressure and confirm I am at 40psi at the...
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    Yamaha 115 4 stroke sputter/stalling. Help!

    My pump is like $250 because I have a 4 stroke. Stinks haha