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Re: 99 Silverado 4.8L P0300 Misfire and Knocking
Posted to Technical Discussion Forum on 5/24/2003

What is actual O2 sensor voltage from sensor 1 at WOT. 800mv is not high enough, must go over 900 mv min to ensure proper fuel deivery. If 800 mv is your actual reading then I would look at power to the injectors or the injectors themselves as the engine seems... Login to read more.