2011 F50 always stalls on the first startup attempt

[dray0151]

pressure sensors

what did the intake pressure not give any read out when cold?
what about the Barometric Pressure/atmospheric pressure sensor,
how far apart were the 2 readings?

I believe the Barometric Pressure/atmospheric sensor was the one that was reading off from the weather station.
29.92 is normal sea level pressure from what I read on line, but then corrected will read a little higher.
the weather station hanging on a wall in my house says it is 30.25 right now here in Texas a few miles from the coast.
On line says it is 29.94

On my 2004 F115 TLRC the intake pressure and the atmospheric pressure both read today at 28.15 but the local station listed it as 29.19? Would this indicate what is an incorrect reading?

[99yam40]

At least they both agree with each other.
Could the reference voltage be a little low causing this? maybe

Maybe Rodbolt can say how accurate these sensors are compared to the local weather station

[rodbolt17]

beats me
but I wont sweat a less than 1 psi reading.
I would go find the issue.
air pressure here at the house may be different from Oregon inlet or the duck research pier, but not by much.

[dray0151]

on the F115 TLRC where is the sensor that reads the atmospheric pressure? I find the one that reads the intake pressure which is on the port side top of the engine

[rodbolt17]

it is the same sensor.
at key on the engine is off so both intake and baro are the same, or should be.
once the engine is started that baro is locked into the ECU for the rest of that key on cycle.

boats do not tend to change altitude much during a key on cycle.

[dray0151]

Good thats what I thought I was seeing from the diagrams, on My YDIS through the TPS was .723, but had an ISC valve opening of 65%. Is that what you were referring to above should be 38 to 40 some % or is that another reading? My reading was on the static test mode.

The PSI weather reading was also from a national weather station reading about 30 miles away thats the closest to me so I would not be to concerned that it is different where i walk.

[rodbolt17]

the F115 is a different monster than the F150.
the original link and sync of the F150 was a failure.
do a fourm search with a thread by high sierra.

[boscoe99]

Do you wear gloves or end up with lots of power residue on your hands?

I ran out to the bay this morning, way too many people out there on weekends.Made me remember why I go during the week normally.
Did not see even one red on the flats. did pick up one undersized blind casting though.
Op sounds like you need to be checking the reference voltage.

But would both of the pressure sensors get the same reference voltage to throw them both off the same maybe?

There is only one manifold absolute pressure (map) sensor. Key on before start it is reading manifold pressure which is the same as atmospheric pressure. Once the engine starts the pressure drops and the read out is then intake manifold pressure.

But definitely check the input voltage to the sensor. Key on motor not running and key on motor running.

Pressure today for most all of NH is at or about 29.90" Hg.

Where is fairdeal? We need some tests done to see to what extent a Yamaha F225 pressure sensor agrees with what is being used at the local aerodrome.

[dray0151]

The sensor is a three wire sensor, pink/green, black and brown. I assume the black a ground but which other wire to put a voltmeter on and what voltage should I expect?

Also what about the ISC valve opening at 65% refered to? All Rodbolt said was it was a different monster than a 150?

[99yam40]

I am getting very confused,
this thread says it is on a 2011 F50

but people are talking about f115s and F150s

[dray0151]

Sorry 99yam thats my fault I asked because I saw some of the same things on my F115 and figured Boscoe or Rodbolt would answer.

[99yam40]

I do not think you are the only one not talking about a F50

I am beginning to wonder if the F50 is a f150 now, or did Rod not realize this was about a F50.
I believe he may have confused the 31.5Hg with a 30.5 Hg reading being normal, and his post on 1 PSI not that big a deal may have been 1"Hg also.
I am not sure about any of this

[99yam40]

Nope different thread, motor, and poster

[boscoe99]

Yeah, I got my number from a local station that's about 5 miles from where my boat is docked. Based on that and the history of the region in general, I think the engine's reading of 31.5 is definitely high. The cold test will confirm, and I'll just go from there.

By the way, what is the elevation of the local station that is closest to your boat? The higher the elevation the lower the atmospheric pressure.

[pstephens46]

Do you wear gloves or end up with lots of power residue on your hands?

I ran out to the bay this morning, way too many people out there on weekends.Made me remember why I go during the week normally.
Did not see even one red on the flats. did pick up one undersized blind casting though.
Op sounds like you need to be checking the reference voltage.

But would both of the pressure sensors get the same reference voltage to throw them both off the same maybe?

Since we can't figure out what motor is being discussed I don't really think we can derail this thread too badly.

Good news here is the reds can be found swarming in the surf. Until they move somewhere else.

Bad news is most are too big to keep