Fuel trim question

[Kevinlenderman]

I have been looking at mY fuel trims on the 01 Isuzu trooper v6 3.5
At idle bank one starts at LONG TERM -10.8 at 800 rpm, once I rev slightly it goes to .6 then by 1300 rpm all is perfect
This truck runs perfect, no warning lights, just playing with my fuel trim data
What would cause bank one to run rich at idle ONLY ON LTFT DATA
Matt always talks about running LEAN FROM VACUUM LEAK

[Importech]

It might not be getting enough idle air flow. Try cleaning the carbon buildup around the throttle body plate.

[Kevinlenderman]

Wouldn’t that cause both banks
Thanks for responding

[jkreutzer]

not enough data to tell what’s occurring… LTFT will not tell you in real time what is going on. Look at your STFT’s and O2 sensor readings. Remember LTFT are a look at the past condition. Make sure engine is at operating temp and O2’s are in closed loop. STFT will oscillate positive to negative 2 to 4 or so at idle. If no codes or readings in the 20’s nothing is wrong. Your looking at data from a past event not your real time idle data.

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