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  1. #1

    Default 1990/305 Engine/Trans Question

    Just had my 1990 Chevy 305 Engine Fuel Pump replaced since it was surging up/down and running erractically. Before this the trans was shfiting very hard from 1st to 2nd,,, seemed to shift a little smoother when it warmed. Now since the fuel pump has been replaced and the engine runs perfect it nows shifts 100% better. Anyway the fuel pump could have done that makes it shift smoother now??? Stumped! Thanks

  2. #2


    YES you have a t.p.s. throttle position sensor that tells the tranny how hard to shift dep. on throttle pos.the weak fuel pump made the motor run weak/ more throttle than nesc. when running strong harder shift

    99 tahoe 2 dr. 4x4 7.4 4L80-e NP246, SAS, dana 60 hp, sterling 10.5 rear, gibson headers, and alot of tricks of the trade !!!!!!IF YOU'RE NOT CHEATING YOUR NOT TRYING!!!!!!!!

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