Question for RodBolt

[03yamaha115]

I just Finished a rebuild on my 03 F115 TLRB 20 HRS on the rebuild. The motor has had a stalling problem when coming out of gear down to idle. Last weekend the motor wouldn't idle it was 44 degrees outside, later in the day the motor acted fine. Yesterday bi cleaned out the ISC valve with brake cleaner and let it soak in PB Blaster for 6 HRS. I reinstalled the sensor and hooked up my laptop with Yamaha YDS software and performed a stationary test I heard the valve move. started the motor and let it reach operating temp on the hose in my back yard. I performed the engine running ISC test the rpms increased to 1400. looked at my data stream and the ISC percent was 74 thought that was a bit high. this morning I cleaned my throttle plates hooked up the YDS and went through the test again ISC seems to be functionally correct the percent came down to 66 and the idle was smoother. I can hear the ISC rattle when I shut my motor off and the ISC isn't hot. I tested fuel pressure when I installed the engine 40 key on engine off 37-38 engine running. I changed the screen on the high pressure fuel pump during the install I took some snap shot data this morning. Would like to know your input on this please.




thank you
Kyle












Save date,November 09 2014,
ECM No.:,68V8591A11,

Diagnosis,
,Code,Item,Result,Condition,
,13,Pulser coil,Normal,,
,15,Water temp sensor,Normal,,
,17,Knock sensor,Normal,,
,18,Throttle position sensor,Normal,,
,19,Battery voltage,Normal,,
,23,Intake temp sensor,Normal,,
,28,Shift position switch,Normal,,
,29,Intake press sensor,Normal,,
,37,Intake air passage,Normal,,
,44,Engine stop lanyard switch,Off,,
,49,Over cooling,Normal,,

Diagnosis Record,
,Total hours of operation,241,
,Code,Item,Occurred,
,,Diagnosis Record is unavailable.,

Engine Monitor,
,Monitor Item,Result,Unit,
,Engine speed,754,r/min,
,Intake pressure,65.30,kPa,
,Intake pressure,19.21,inHg,
,Atmospheric pressure,1009.5,hPa,
,Atmospheric pressure,29.9,inHg,
,Ignition timing,ATDC 4,deg,
,Battery voltage (12-16),14.60,V,
,TPS voltage (0.5-4.5),0.728,V,
,Throttle valve opening (0-90),0.7,deg,
,ISC valve opening,66,%,
,Fuel injection duration,2.86,ms,
,Water temperature (below 90),61.7,°C,
,Water temperature (below 194),143.0,°F,
,Intake temperature (below 70),27.1,°C,
,Intake temperature (below 158),80.9,°F,
,Engine stop lanyard switch,OFF,,
,Shift position switch,ON,,
,Oil press switch,OFF,,
,Dual engine system switch,OFF,,

Data Logger[Engine operating hours according to engine speed],
,Engine speed,Time[h],
,- 1000 r/min,53.3,
,1000 - 2000 r/min,24.3,
,2000 - 3000 r/min,12.4,
,3000 - 4000 r/min,76.0,
,4000 - 5000 r/min,71.4,
,5000 - 6000 r/min,3.9,
,6000 - 7000 r/min,0.0,
,Engine hours,241,

Data Logger[Data comparison graph],
,Engine speed[r/min],Battery voltage (12-16)[V],TPS voltage (0.5-4.5)[V],Water temperature (below 90)[°C],Intake pressure[kPa],Oil press switch[0:OFF 1:ON]
,900,14.43,0.72,29.6,63.2,0,
,800,14.58,0.72,36.0,65.1,0,
,750,14.43,0.72,65.0,63.7,0,
,700,14.50,0.72,63.3,65.6,0,
,750,14.58,0.72,60.8,65.6,0,
,850,14.58,0.72,32.4,62.2,0,
,900,14.72,0.72,29.2,64.7,0,
,800,14.50,0.72,33.3,64.7,0,
,750,14.79,0.72,57.1,64.2,0,
,700,14.58,0.72,59.3,66.6,0,
,750,14.65,0.72,60.0,64.7,0,
,750,14.72,0.72,61.7,65.1,0,
,750,14.65,0.72,60.0,66.1,0,










Save date,November 09 2014,
ECM No.:,68V8591A11,

Diagnosis,
,Code,Item,Result,Condition,
,13,Pulser coil,Normal,,
,15,Water temp sensor,Normal,,
,17,Knock sensor,Normal,,
,18,Throttle position sensor,Normal,,
,19,Battery voltage,Normal,,
,23,Intake temp sensor,Normal,,
,28,Shift position switch,Normal,,
,29,Intake press sensor,Normal,,
,37,Intake air passage,Normal,,
,44,Engine stop lanyard switch,Off,,
,49,Over cooling,Normal,,

Diagnosis Record,
,Total hours of operation,241,
,Code,Item,Occurred,
,,Diagnosis Record is unavailable.,

Engine Monitor,
,Monitor Item,Result,Unit,
,Engine speed,808,r/min,
,Intake pressure,64.11,kPa,
,Intake pressure,18.82,inHg,
,Atmospheric pressure,1009.5,hPa,
,Atmospheric pressure,29.9,inHg,
,Ignition timing,ATDC 4,deg,
,Battery voltage (12-16),14.60,V,
,TPS voltage (0.5-4.5),0.728,V,
,Throttle valve opening (0-90),0.7,deg,
,ISC valve opening,67,%,
,Fuel injection duration,2.88,ms,
,Water temperature (below 90),60.8,°C,
,Water temperature (below 194),141.5,°F,
,Intake temperature (below 70),27.6,°C,
,Intake temperature (below 158),81.6,°F,
,Engine stop lanyard switch,OFF,,
,Shift position switch,ON,,
,Oil press switch,OFF,,
,Dual engine system switch,OFF,,

Data Logger[Engine operating hours according to engine speed],
,Engine speed,Time[h],
,- 1000 r/min,53.3,
,1000 - 2000 r/min,24.3,
,2000 - 3000 r/min,12.4,
,3000 - 4000 r/min,76.0,
,4000 - 5000 r/min,71.4,
,5000 - 6000 r/min,3.9,
,6000 - 7000 r/min,0.0,
,Engine hours,241,

Data Logger[Data comparison graph],
,Engine speed[r/min],Battery voltage (12-16)[V],TPS voltage (0.5-4.5)[V],Water temperature (below 90)[°C],Intake pressure[kPa],Oil press switch[0:OFF 1:ON]
,800,14.58,0.72,36.0,65.1,0,
,750,14.43,0.72,65.0,63.7,0,
,700,14.50,0.72,63.3,65.6,0,
,750,14.58,0.72,60.8,65.6,0,
,850,14.58,0.72,32.4,62.2,0,
,900,14.72,0.72,29.2,64.7,0,
,800,14.50,0.72,33.3,64.7,0,
,750,14.79,0.72,57.1,64.2,0,
,700,14.58,0.72,59.3,66.6,0,
,750,14.65,0.72,60.0,64.7,0,
,750,14.72,0.72,61.7,65.1,0,
,750,14.65,0.72,60.0,66.1,0,
,700,14.65,0.72,60.8,67.6,0,

[boscoe99]

Intake manifold pressures seem on the high side. Take a look at the download in this link which are indicating approximately 12" Hg.

http://www.yamahaoutboardparts.com/f...p-th24499.html

[rodbolt17]

I am with Boscoe.
intake pressure at idle is way high.
look for intake air leaks.
or compare the atmospheric pressure with your local weather channel.

[nitrousmikey]

smoke test the engine at a local mechanics shop to find vacuum leak also unplug the iac valve when it is idling correct and se if the varying idle speed still occurs.