2005 f250 yamaha

[wavetamer]

my 350 hour f 250 4 stroke seems to have developed a delay when you give it throttle, other than that it runs perfect. injector issue ??? was thinking of running injector cleaner through it to see if it helps , wont be able to get to a tech for a month or so , any one else had this problem

[wavetamer]

from idle to increased RPM

[fairdeal]

injector cleaner can't hurt.

Personally, I'm amazed that an engine with
two accelerator position sensors,
two throttle position sensors,
and an electronic motor-driven throttle valve
works as well and reliably as it apparently does

[boscoe99]

Those electrons are quick.

[wavetamer]

so im on the right track in thinking its an injector issue, the engine does run smooth, just a delay from idle to increased RPM

[boscoe99]

On a ten/eleven year old motor the injectors could very well be in need of a cleaning. But I would also inspect the fuel pressure regulator output. Fuel pressure is lowered with the throttle at idle. Manifold pressure is low. Fuel pressure increases as the manifold pressure increases with the throttle being advanced. If the regulator is a bit balky/slow at increasing fuel pressure at the same rate as the manifold pressure increases the motor will be deficient of gasoline. This can cause the motor to stumble or balk upon acceleration.

[pstephens46]

injector cleaner can't hurt.

Personally, I'm amazed that an engine with
two accelerator position sensors,
two throttle position sensors,
and an electronic motor-driven throttle valve
works as well and reliably as it apparently does

Can anyone explain the function of an accelerator position sensor? In regards to a marine motor? As compared to TPS?

[boscoe99]

Can anyone explain the function of an accelerator position sensor? In regards to a marine motor? As compared to TPS?

The TPS tells the ECU the position of the throttle valve or if the throttle valve is being moved to the open position or the closed position, and at what rate.

Let's start with a completely mechanically con*****ed motor, such as the F225 that Mr. fairdeal owns. It has six mechanical throttles and one TPS. His control cables connect to the motor and physically move the throttle valves as he pushes the throttle forward and aft. As the throttles open and close the TPS tells the ECU what he is doing and they make changes to the timing, fuel delivery, etc..

A next generation mechanically con*****ed motor with an accelerator position sensor (APS) has the mechanical throttle cable connected to it. The APS is connected electrically to the ETV, or Electronic Throttle Valve. As the throttle handle is moved forward and aft it mechanically moves the APS. The APS then electrically makes the ETV open, close or stay the same. If opening or closing, at what rate. The ETV has a TPS embedded within it and that TPS tells the ECU what is happening to the throttle valve so the ECU can make some needed changes.

Then comes the fully digitally con*****ed model. The throttle handle has the equivalent of the APS embedded in it. The throttle handle moves forward and aft, moving the APS, which then tells the ETV how it is being moved and the ETV moves accordingly.

[pstephens46]

Thank you for the reply. The term acceleration had me confused. Thinking in terms of rate not position.

[boscoe99]

Thank you for the reply. The term acceleration had me confused. Thinking in terms of rate not position.

Think of the accelerator pedal on most new cars/trucks. It can be analogous to the accelerator position sensor. You move the accelerator pedal by pushing down with your foot and a sensor on the pedal tells the throttle valve on the motor what to do. Now if you ran a mechanical throttle cable to the accelerator pedal and moved the accelerator pedal with the throttle cable it would be the same thing as on some outboard motors.

[pstephens46]

My Nissan has a water cooled throttle body. I assume it also performs the function of the ICV. Is the throttle body water cooled on the latest Yam digital motors? My understanding is they have no ICV.

My apologies to the OP for the hijack....I'll bow out now..

[panasonic]

the tps tells the ecu the position of the throttle valve or if the throttle valve is being moved to the open position or the closed position, and at what rate.

Let's start with a completely mechanically con*****ed motor, such as the f225 that mr. Fairdeal owns. It has six mechanical throttles and one tps. His control cables connect to the motor and physically move the throttle valves as he pushes the throttle forward and aft. As the throttles open and close the tps tells the ecu what he is doing and they make changes to the timing, fuel delivery, etc..

A next generation mechanically con*****ed motor with an accelerator position sensor (aps) has the mechanical throttle cable connected to it. The aps is connected electrically to the etv, or electronic throttle valve. As the throttle handle is moved forward and aft it mechanically moves the aps. The aps then electrically makes the etv open, close or stay the same. If opening or closing, at what rate. The etv has a tps embedded within it and that tps tells the ecu what is happening to the throttle valve so the ecu can make some needed changes.

then comes the fully digitally con*****ed model. The throttle handle has the equivalent of the aps embedded in it. The throttle handle moves forward and aft, moving the aps, which then tells the etv how it is being moved and the etv moves accordingly.

FADEC.....

[fairdeal]

you aviation guys must know lots of fly-by-wire stories

I have little knowledge of it, but am fascinated by Air France 447

[pstephens46]

Lack of high altitude flight training. No autopilot at 30 something 1000 ft, oh sht what do we do now?......French are better than Koreans. There is a list of Asian airlines that Gulfstream employees are not allowed to use.

Not a racial thing. Culture of pride, "don't question me"

[boscoe99]

I am waiting for a Yamaha wireless system. The control box goes home with you at the end of the day. It mounts into a docking station just for power.

If we can fly drones over Afghanistan from here in the US surely we can control an outboard motor from 20/30 feet away.