Stalling Yamaha F150

[rodbolt17]

pokin and hopen wont fix it.
its NOT a sensor.
its the way the ISC reacts.
its a common issue.
there is a chart for normal barometric pressure at 5000Ft.
its simple to check.
hook up the laptop, turn the key on.
read the baro pressure then google your local weather channel and see if the two agree.
the higher the altitude that the baro sensor tells the ECU its at the leaner the A/F mix gets.
but typically it doesnt affect it much below about 1800 RPM.
trust me my 07 F150 did this out of the box.
its rather embarrassing for a Yamaha Master Technician to have his brand new F150 stalling while manuvering.
I had to figgure it out.
bad enough my service manager had to tow my other boat with an 07 175 E-TEC home with his new 90 yamaha.
I heard about that a LOOOOONGG time.
that off idle stumbe can be corrected if the techs actually understand what the system is doing and why.
and some times ya simply gotta fake out the stupid ECU.
remember, at key on power the MAP sensor is going to take a snapshot of barometric pressure. that is locked for that key on cycle.
if that is wrong then the manifold abosolute pressure while running will be wrong.
coolent temp is easy to fake out, its a simple thermistor.
easily faked with a 50 cent radio shack resistor.

[high sierra]

stalling

Rodbolt, I'll give this advice to them. Thanks high sierra

[high sierra]

stalling

rodbolt, the pressure is different. The have found it to be lower than all the other engines they have worked on lately. MAP sensor? high sierra

[rodbolt17]

could be the sensor, could be the wiring.
does this engine use command link?
if it does are you using the speed and water pressure transducers?

remember this map sensor does TWO things. ONE is it locks barometric pressure at key on engine off as a reference. typically boats dont change altitude much between key on cycles.
TWO it provides the ECU with data about manifold absolute pressure.
MAP is simply the inverse of engine vacum.
if you expect a normal 4 stroke to idle at 17-20" Hg vacum them expect to see 12 to 15 psi on the map.
the farther the trottle is opened the closer to 0 PSI the map is going to indicate.
at WOT there is almost NO difference between atmospheric pressure and manifold pressure.
as the throttles close the pressure in the manifold is going to be lower than barometric pressure.
yes its confusing, the difference between MAP and engine vacum. couple that with several ways to monitor it and several different software programs and it gets almost insane.

[high sierra]

stalling

Rodbolt, I just reread your solution after some stiff coffee and now I know what you mean as to how to fix it. It should only take 5 minutes to do it.I now know what the dealer did after your fix therefore it didn't work. Right now they are looking for a problem that I now believe is possibly caused by the motor being " broken in" and is possibly out of range of the parameters of one of the sensors. This would cause the engine to run too lean, therefore stalling at idle. They are looking for a malfunction which I think is a design flaw. Luck. Will advise. high sierra

[rodbolt17]

not a design flaw.
its simply trying to design an engine that works at se*****l and 5000 ft without having a clue what kind of hull or rigging its gonna have.
if a sensor was out of range you would see a code on the laptop.
typically if a sensor fails or goes out of range idle timing is fixed at 10*BTDC and idle fuel is fixed rich and idle speed increases to about 1000 RPM.
depending on the sensor top speed may or may not be reached.
typically that off idle stumble.
the annoying one that occurs with small throttle movements below 1000 RPM, are a function of the TPS,ISC and the mechanical setting of the throttle shutters.
my F150 would run fine as long as from idle to crusie the throttle was moved rapidly.
its was only when manuvering and making *****ing speed adjustments that it stalled.
hopefully one day the F150 will get a single throttle shutter intake.

[high sierra]

Still stalling

I went to the dealer today and with 2 mechanics went through the whole procedure. Still stalls ! We can get an rolling idle and that's about it in a tank. Now Yamaha ( Atlanta) wants us to do an on water diagnostic at idle , under load and wide open. It's 25 degrees and snowing today. The nearby mountains got 10 feet of snow. The weather channel is up there now . The lake doesn't freeze but damn is it cold out there. Merry Christmas

[high sierra]

Success

The tech arrived from Yamaha yesterday afternoon to work on my 150 Yamaha. He found out the machine that the dealer was using was out of spec and wouldn't give reliable readings so he used his own diagnostic equipment. He soon had the idle working and "reportedly" not stalling. He also found the balance shaft was rattling badly and was about to fail which would have destroyed the engine . The new shaft has an improved oiling system and tighter clearances so no more failures , they say. Yamaha is fully aware of the problem and is working on the modifications . Parts are on order. Tech will be back to install the parts. We will test it on the lake when done. I will advise as to the results. high sierra

[rodbolt17]

pee on my leg and convince me its raining.

the problem was not out of spec equipment.
there are NO specs.
its simply a digital multimeter and the laptop.

however the person looking at the data can be out of spec.

good they found the balancer, if you look back I warned you of that gator at least twice.

its also why I dont ever ask yamaha to send anyone.
if I have to ask an RTA it means I am lax on my training and knowledge.

the balancer has been an issue on all f150 engines prior to the 08 run.
the balancer is on its 3rd modification.
ALL F150 owners need to learn to listen at the idle sounds.
balancer will give many hours of notice before it fails.

you may wish to hunt for a dealership with trained techs.
next time your there ask the owner to see the training certificates.
two stroke systems.
fuel
electrical
drive train
four stroke
advanced four stroke
then Master technician.
if they are not there gently remind them that yamaha courses in Kennesaw Ga are free.
I get to go back to drive train this year because they are going to offer the F350 case.

[high sierra]

stalling

Rodbolt , I do want to thank you for the information and encouragement to get this fixed. The dealer has NO one with the training needed to do this . They are a new dealer and will probably end up with the only dealership in the area. The other dealer with one trained person is so bad , I think Yamaha is working to get another dealershiip in operation before they yank the franchise.
I can't believe the solution to the stalling was only the throttle plates and llinkeage as both myself and the mechanic who is trying very hard did that same operation. I think a little smoke is being blown up my kilt. The tech showed the dealer they badly needed training and there is serious discussions on that very subject. They have never worked on a F150 they are so new.
How come Yamaha hasn't notified every owner of the problem? If this wasn't under warranty , I'd be talking to the Honda dealer.
If there was something to be learned from this , DON't buy from a bad dealer or no dealer in your town no matter what the brand. Waiting for parts, high sierra

[efforbCotourn]

Please HELP!!!

Sorry please dell this topic...

[Braskgaks]

New Member

Thanks for the approval! I look forward to learning from everyone here, and hope to contribute as much as I can.

[rodbolt17]

not only does the technician of today need training they also ned to read and understand EFI and DFI basics.
covers ALL efi and dfi induction systems.
without it your sunk.
the stalling issue isnt on ALL F150 motors and I had to fight mine on my own in the summer of 07.
so far any and all balancer failures have been covered by yamaha regaurdless of warrenty status.
all they ever ask me to do is inspect the drive gear to see if its a balancer or a powerhead assy.
the yamaha training is nice but a week long course that will cover many models,coupled with flat wrong diagrams occasionally, a week is not enough time to train a tech UNLESS that tech already has read and has a basic understanding of how and why EFI systems work AND what the function of all sensors are AND why they are there AND how they interact with the inputs to and the outputs from the ECU.
at 700+ dollars a copy I dont stck balancers either.
takes 1.5 hours or less to swap the balancers.
balancer is simple to change, there is even a tech bulliten with a revised procedure that negates pulling the flywheel.
there again I figgured that one out years before it got published.
its a simple matter of mechanical timing of a set of gears.
glad ya got it fixed and dont give up on the new guys.
I have seen issues with Honda dealers and jonnyrude dealers and mercury dealers as well as a few others in the past 30 some odd years at this type work.

[high sierra]

stalling F150

Well the Yamaha has been worked on by the shop and the Yamaha West
Coast area TECH . I took it on a test on the lake, 20 degrees and total fog and the damn thing continued to stall and eventually quit. After much turning over and checking cables and hoses, it started but the 8hp Yamaha finally got us back to the dock. Now we have a fuel problem plus the stalling problem. The motor was much worse.
Upon returning home , I checked under the hood and they had installed the fuel filter backwards. The Yamaha tech had also set the TPS at .76 and that screwed up the overall running.
I reset the tps and the idle improved somewhat. I could hear a hissing sound like a vacuum leak around the throttle bodies so I sprayed some throttle body cleaner between the 2 TB's and the idle went up and smoothed out for 30 seconds. Does the ISC have an air intake on it vented to atmosphere, or does it get air from the intake manifold and plenum? high sierra

[rodbolt17]

slow down.
back up.
your getting jiggy.
the system is desined to work with the shuuters fully closed and all idle air via the ISC which gets its air from outside the intake.
however in real life sometimes we fake out the ISC by cracking the shutters.
the ECU nor the ISC know it happened.
but it places the ISC valve in a more responsive range of opening.
same setup the F200/225 uses.
you may or may not have 2 or more issues.
its a high probibility now you have technician induced issues.
the .76 V on the TPS, wont have jack squat to do with overall running.
its very very barely out of spec and about what my personal F150 runs at idle now.
its tough to fight two issues, much less when a tech toss's a tech induced issue.
dont wish to take this to PM, but PM me.