When I start the engine it idles perfect 600. After running the boat for a while it idles between 8-900. If I shut the engine down and start it back up it idles fine at 600. When running the engine and runs perfect. Any thoughts? Thank you.
F250 Yamaha 2005 idle
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Doc Stressor
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It's likely a sensor that sending an intermittent bad signal. I would suspect the throttle position sensor. These often throw a code each time they fail.
I would take it to a dealer and have them download the log and any warning codes.
I would take it to a dealer and have them download the log and any warning codes.
Doc Stressor
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Before you start ordering parts, you really need to run a diagnostic and look for codes. In addition to the TPS, there are also accelerator position sensors that could be the source of your problem (although I doubt that would give your symptoms). The other possibility is air leakage in the throttle valve cylinder head. The Yamaha shop manual for my engine says to look for a trouble code first, then check the O-rings and gaskets in the intake manifold, surge tank, an throttle body.
I had a certified master Yamaha technician diagnose the engines and the only code that came up was 72 cam position sensor at 1000 hrs. I now have 1080. I swapped the sensor with the other motor same problem so it's not the sensor. Anyone have any thoughts. Thank you
I had a certified master Yamaha technician diagnose the engines and the only code that came up was 72 cam position sensor at 1000 hrs. I now have 1080. I swapped the sensor with the other motor same problem so it's not the sensor. Anyone have any thoughts. Thank you
It could be anything from a bad fuel pump pressure regulator and or pump to a bad IAC motor, TPS sensor, or MAP sensor. Hard to diagnose without the laptop out. I would have had the technician check the engine parameters (live data) on each motor and compare. Too many electronics on these EFI motors to just guess.
I know it's unlikely but pull the motor cover off and take a look at the throttle linkage setup. Could be something simple as that.
I know it's unlikely but pull the motor cover off and take a look at the throttle linkage setup. Could be something simple as that.