Complicated Issue- Yamaha 2003 200hp

[Galbreath]

We've been working on this for a while now. The issue is engine wont run above 2,500 RPM with load.

We've cleaned out the gas tank and put cleaner and premium gasoline in, right now I'm trying to figure out how to get out the spark plugs/ignition coil (unclear as to which my engine contains) and figure out if one is busted.

Once this step is completed, getting the fuel injectors checked would be the next step.

The engine is a Yamaha LF200A 200 Horsepower 4 stroke 2003 model. If anyone can give advice on removing the plugs/coils or has had similar issues, be good to know.

 

[Capt Ken]

Re: Complicated Issue- Yamaha 2003 200hp

First, without the diagnostic computer system to check it out, you are wasting your time trying to figure out this one. The newer engines are not something the shadetree person wants to get into. Sounds like the system has a problem and its falling back into the failsafe mode.

 

[rodbolt]

Re: Complicated Issue- Yamaha 2003 200hp

that engine is designed to run on regular unleaded, premium actually makes it lose power.
the coils are located behind the rear plastic cover thats retained with 4 5mm hex bolts.
they rarely fail.
the plugs are behind that cover as well.
the diagnostic test lamp costs about 70 dollars and is the minimum diagnostic equipment you need, the lap top and certain test harness's along with a digital voltmeter is better.
a fuel rail pressure test gauge is another mandatory step to monitor rail pressures.
its a very simple EFI system and the ign system is a very simple TCI setup.
however without the proper manuals and the minimum test equipment AND the shop service manual your wasting time and money.
the coils are 135 apiece, the low pressure fuel pump is 500, the high pressure is 700, the oil pressure switch is 300+. see where I am leading ?
trouble shoot first, isolate the subsystem that failed then isolate the component in the subsystem and its fixed right first time everytime.