Question for the pros! 2003 4 stroke 150 Yamaha

[Gary H NC]

I have a surging at idle problem that happens on the muffs and in the water.
Also sometimes it just dies at idle too.
At higher rpms it runs like a top.

All filters have been replaced,injectors sent off and cleaned,spark plugs replaced,ect..

Could this be a sensor problem of some type?

 

[rodbolt]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

need to know the TPS voltage and the ISC valve percentage, even better can you do the active test with the laptop?

 

[Gary H NC]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

I wish i had the software to do it Rodbolt.
I was trying to avoid the 100 dollar fee at the dealer just to plug it in.

I can check the TPS voltage with my multi-meter if that helps.
Any tips on the tests would be appreciated..

 

[rodbolt]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

no way around it you MUST have the correct diagostic tools AND know what and why they appear on the screen
you can buy the kit for 300 dollars.
if your going to monkey with stuff ya gotta buy the bananas.
you simply gotta watch what the ISC,MAP and TPS sensors are doing as well as injector on time and ign timing while its trying to die.
the ECU is going to attempt to make it idle at about 650, it mainly relies on the ISC valve to vary the intake air. the TPS tells the ECU that the throttles in a certain position and the map sensor gives it engine load.
from there the ECU can make fuel injector on time vary and ign timing vary as well as add or subtrct intake air vi the ISC valve.
my guess is the link and sync is off or its set like the factory settings.
what I typically do is open the throttle shutters slightly,after syncing them, and watch the ISC, when it hits about 40% stop and reset the TPS to about .7.
this gives the ISC a faster reaction time and more range.
but this can only be done after verifying nothig is broke.
we find it gets rid of that annoying off idle stumble and die.

 

[Gary H NC]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

Thanks Rodbolt.
I rarely work on Yamaha but 300 is not bad for the setup.
Any suggestions where to buy it?

I found it listed online for about 500 bucks...ouch.

 

[rodbolt]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

dealer cost is 295,plus the dealer markup which can be whatever.
they are backordered currently, shiiping date is like 08 aug 2010.
our USB cable finally puked so I ordered 2 kits.

 

[Gary H NC]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

Is this the same one? Kind of pricey though.

 

[Gary H NC]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

Bump...link added.
http://www.simyamaha.com/Yamaha_Diagnostic_System_Software_p/ydskit1.33.htm

 

[rodbolt]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

yep, thats the latest and greatest version.
markup is kinda tough but yamaha doesnt have an MSRP for tooling.

 

[sdsaw]

Re: Question for the pros! 2003 4 stroke 150 Yamaha

Just a thought...
Have you also checked your thermostat?