truck bucking

When I'm at a normal rpm for driving say 3rd gear ( manual 5 speed ) 30 mph my truck will start to buck and jump till I give it gas. I have given it a
tune up tried fuel cleaners, I need help can't figure it out!
--
jmo

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What model, year and engine does vehicle have? ----------------- The SnoMan www.thesnoman.com
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SnoMan wrote:

Chevroler, 1992, 5.7 V8
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jmo

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Throttle Position Sensor?

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