2001 SX225 Intake Air Temp Sensor

[Inpursuit]

I have been having a rich condition ever since I got this motor and finally got around to checking what I thought might be the problem.
The problem I 'm having is that the motor will run fine in the morning when it's cool but in the afternoon when it warms up it runs very rich so my gut feeling is that the intake air temp sensor may be the problem or at least some of the problem so I checked it per the Yamaha service manual at it shows it should be from 3.4-5.3V with the key on but when I checked mine it shows 2.4V so is that enough of a difference to cause a problem?
I also put a hair dryer on the sensor and the voltage dropped and i'm also wondering if that is normal for it to go down.
Thanks: Frank

[boats.net]

That could be the problem, the most common thing we see is ruptured diaphrams in fuel pumps, stuck themostats and leaking injectors.

[Inpursuit]

One thing I just remembered but I don't know if it has anything to do with this problem.
Last fall when I was winterizing this motor I had it running on the hose and it would miss maybe once ever 30 seconds so for some reason I grabbed the primer bulb and pumped it up and held it under pressure and ever time it would miss I could feel the pressure in the bulb drop suddenly.

[99yam40]

Have you checked the fuel pumps?

[Inpursuit]

Have you checked the fuel pumps?

I rebuilt them last spring