Re: Jerking at 55mph
clean and/or change the sensors on the engine too. maf, iac, temp sensor, throttle position sensor, air charge sensor and o2 sensor too as someone mentioned. could even be a bad computor too. or is this carbereted engine? sea foam it good too. half can down the vacumm hose and other half in gas tank. get a good scanner and see what codes it throws. hope this helps.
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