Stalling Yamaha F150

[high sierra]

I have a stalling 2007 YAMAHA F 150 four stroke. It stalls as the throttle is applied just after you have put in gear. Does the same thing when you hold the ****on down and bypass shift engagement. Also stalls when you come down in RPM when approaching the dock. Did a synch and link, set the vacuum on the four cylinders closely, and adjusted the throttle position sensor to .7 volts. I already replaced the tps thinking it was the problem. Minor improvement in voltage readings. Was adviced there was a chance it was the idle speed con*****er. Does anyone know if the sensor, which is just a solenoid that lets more air into the manifold at idle could be the problem. Does the solenoid move in and out when not running and you turn the key on when the sensor is laying on the top the of the motor still connected? Can it be checked this way? I have also checked the shift interupt switch to no avail. Idle is perfect , until you engage the throttle. Thanks , high sierra

[boats.net]

May need the idle control valve(63P-1312A-01-00) cleaned or replaced.

[high sierra]

stalling

Thanks , I think you are right. I finally took the motor to a dealer who will do it on warranty and so far they can't find the problem even with the Yamaha diagnostic. I have suggested the Idle Speed Con*****er as the manual likes to call it. I quit working to find the problem when I saw the price of that particular part. Thanks for your input on the problem. high sierra

[rodbolt17]

its because the problem is a ghost.
there is a fix.
its very simple.
takes about 10 minutes and a digital multimeter.
do you have a service manual?
however there are larger gators that are gonna bite that F150.
you will find it has nothing and everything to do with the ISC ya just dont need to touch the ISC.

[high sierra]

stalling

rodbolt17, I have a digital meter and the factory repair manual. I've already set and reset the TPS many times . The manual doesn't call for a setting on the ISC. There is none. Tell me the simple fix if you will. What other gators plague that motor? I'm into preventative maintenance. Your last line has me scratching my head. Thanks for any help. high sierra

[rodbolt17]

the stalling issue is easy.
adjust ALL 4 throttle shutters closed.
means back off the top one, adjust the lower one so all 4 move the same.
from here we are gonna deviat from the manual a bit.
now you MUST have a means to monitor TPS voltage.
watching it on the lap top is better.
howver what we are going to do is fake out the ECU.
can you monitor TPS voltage?
if you cannot I will go no farther.

[high sierra]

stalling

Yes ,I can monitor the TPS voltage. I have the harness to connect up to my voltmeter. high sierra

[rodbolt17]

what we are going to do is actually mis adjust the TPS.
insure all shutters are fully closed, then using the top screw slightly open all 4 shutters,then set the TPS voltage.
what you want is the ISC to close down to about 40% instead of its typical 60-65%.
the off idle stalling on the F150 is common, drove me nuts 3 years ago on my 07 F150.
the biggest issue on the F150 is balancer failure.
this failure will give many hours of warning, if you listen.
starts out as a washing machine sound at idle.

[high sierra]

stalling

Gentlemen, the dealer has the boat now and hopefully has a cure. The mechanics are young and trying hard to learn. They may replace the ISC, which if it is malfunctioning will solve the problem. If it isn't the ISC, I will try to work with them using the "Rodbolt adjustment" . Pretty smart! Im afraid this is well beyond them for standard servicing. I will let you guys know what the outcome is. Thanks again , high sierra

[rodbolt17]

if this is an actual yanaha dealership have the call the RTA.
they can supply it.
doubtfull the ISC is bad and you will most likly have a spare 300dollar part.
at engine shut down you will hear the ISC resetting for the next start cycle, thats the rattling sound you hear immediatly after key off.
it can also be tested both dynamically and staticly with the laptop.

[high sierra]

voltage

Rodbolt, what was the voltage reading after you released the throttle plates back to their closed position? What is the RTA? high sierra

[rodbolt17]

RTA is regional tech assist.
its avalible to Yamaha dealers.
the TPS voltage when the adjustment is done is still .7 volts, we are not changing the TPS feed back, we are faking the ECU.
the ECU has no clue we just mechanically added air.
all it will see is an increase in RPM and will close off the ISC to achive a stable idle at about 650 RPM.
it also causes the ISC to run in the 40-45% range as opposed to the 55-65% range.
makes it able to react faster and cant shut down the air.
normally we set all the shutters then the TPS using the shutters, this time we wont.
I had to figgue it out on my personal F150 in aug of 07 when I bought it.
its a fairly common problem.
its also embarrasing to wear a Yamaha Master Technician hat while at the helm of my 21 seapro that just stalled while manuvering around the harbor.
so if this is an actual Yamaha authorized facility they will have access to the RTA and a laptop.

[high sierra]

Thanks

Thanks. I will advise. high sierra

[high sierra]

stalling 150 Yamaha

Well, the Yamaha diagnostic computer turned up zip, nothing , zero. All the parameters are within their ranges and the stalling continues. In fact it's getting worse.The dealer has changed the tps, the isc, the sensor for the manifold and the main computer(ECM) and nothing has changed. The tried the Rodbolt method and it did'nt work. They have searched for air leaks all over the engine and there were none. 4 Techs at Yamaha in Atlanta cannot seem to come up with an answer either. They are now saying running the boat with the diagnostic hooked up should be done on a lake nearby (which is a 100 mile trip). The motor runs well once you get past idle. Their is a disparity in the intake vacuum, BUT, we are at 5000 feet altitude and that makes them completely unsure as to what it should be. So much for Yamaha 's much vaunted warranty and skills. The dealer is definitely trying and I have been working with them as much as possible without stepping on their toes. I will advise. high sierra

[high sierra]

Stalling 150

I have a feeling that a sensor , possibly a temp sensor is sending a faulty reading to the computer and it is sending a signal to lean out the mixture causing the lean idle. The dealer is going to try that next. They are slowly stripping a brand new 150 of all its' sensors. Got to give them credit. high sierra