2003 yamaha 250 ox66 rich condition

[PAULDIDIT]

i HAVE A 2003 YAMAHA THAT SEEMS TO RUN RICH AFTER IT WARMS UP AND GOES INTO CLOSE LOOP.
i'VE CHECKED THE FUEL PRESSURE AT THE RAIL 35 -36 PSI RUNNING.
I'VE CHECK THE BARO SENSER &TPS SEEM TO BE IN RANGE.
AND THEN I CHECKED THE O2 SENSOR i COULDN'T GET IT TO COME ABOVE .3 VOLTS RUNNING AND WHEN I TAKE IT OUT AND USE A PROPANE TOUCH ON IT THE BEST IT WILL COME UP TO IS .4 VOLTS AND THE HIGH SIDE .
DO YOU THINK THE O2 SENSOR IS BAD AND CAUSING THE RICHER CONDITION ?
I KNOW ON VEHICLES THAT VOLTAGE WILL TELL THE ECM TO RICHEN IT UP AND OR THROW A CODE, i WISH THIS MOTOR HAD A DATA STREAM SO i COULD LOOK ATY EVERYTHING WHY ITS RUNNING.
IF YOU COULD GIVE ME SOME IDEAS THAT WOULD BE GREATLY APPRECIATED
PAUL

[rodbolt17]

did you check the lift pumps for leakage?
does the engine come up to temp?
did you check the O2 sensor heater voltage?
did you actually clean the O2 sensor?

[PAULDIDIT]

No; I didn't check the heater voltage

yes; i did clean the o2 sensor

No; I didn't check the fuel pump for leakage, the electric one or the mechanical?

Yes; the engine does get up to temperure, with the infared gun it says about
143 degreese at idle.

[99yam40]

I am sure it was the mechanical pump he was talking about

[rodbolt17]

rail pressure. what is it at the failure RPM and load????.

don't care what your infa guns say, what does the ECU see???????

when you cleaned the O2 sensor did you TEST the sensor output voltage??????

that motor tends to eat lift pumps.