At low speed or when coming to a stop car hunts

1 have a 97 f150. When coming to a quick stop it idle erratically almost dying. Also does it when going slow and coming to stop. I have changed Throttle position sensor and Idle air control valve. Still does it. Also the rpm gauge acts crazy sometimes- I believe thats just a bad gauge. Was looking at fuel trim doesnt seem quite right. At 57 mph rpm 1756 stftM!-(-3.4) LTFTM1 (+30.4) STFTRM2- (-2.2) LTFTRM2- (+31.2) 02 SENSOR S11 (.715) 02 S12 (.125) 02 SENSOR S21 (.52) 02 S22 (.55)

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[Richard KirshyParticipant]

By the looks of your LTFT’s
Your engine is running extremely lean.
Could be a vacuum leak, clogged injectors,weak fuel delivery.
Suggest you first try smoking the intake and check for vacuum leak(s)if thats checks out good, next check your fuel pressure and make sure it is with in specs.

• This reply was modified 3 years ago by  Richard Kirshy.

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