Motor won't speed up in warm up position

[loriboudreaux]

Please Help....

I have a 2004 Yamaha 2 stroke 200 HPDI motor. I hooked it up to a separate gas tank to run fuel injector cleaner through it. In the warm up position it will only run at idle. If I try to increase the throttle the motor stops, but if you shift it into forward the motor will speed up. Just wondering what would cause it not to speed up in neutral???

[Sequoiha]

HPDI wont accelerate in neutral,, has to be in gear... its in the ecm and shift switch,,

[loriboudreaux]

can you please explain this to me. i have two of these motors on the back of my boat and have always used the warm up lever when starting them. they will normally rev up in neutral as with any other motor i have ever owned. at this time the port side motor still does so without any problem.it was just this weekend that i had this problem for the first time. thanks for any advice on this.

[Sequoiha]

If you have to use a warm up lever on a HPDI then you have a running issue,, these engines are mapped to run at a higher rpm during cold start, and remain there till they reach 114 degrees, then idle down, you should never have to accel a fuel injected engine to keep it running.

[loriboudreaux]

these motors were installed in place of carbureted v-max 150's and the controls and gauges all stayed from those motors. i had never had any problem starting or running beforeso i am really confused at what could have happened to cause this problem. i have had these motors for four years so far and they have very low hours on them.

[Sequoiha]

There is one thing I say to anything that isnt working properly,, It was till it wasnt,, 2004 engines and you have had them 4 years, have you done any maintenece,, they idle on 4 cylinders in neutral, numbers 2 and 3 do not fire,, so if you have a bad plug in any of the other cylinders then you are only idling on 3 cylinders,, it seems it time for some basic diagnostics,, and if you dont know how HPDI's work I suggest you find some one that does,, or you will pull your hair out..

[rodbolt17]

ill second the motion.
also when in N position and speeds above 1500 RPM you lose two more cylinders for a total of 4 cylinders shut down.

the warm up lever should not be used for starting ANY fuel injected yamaha outboard.