ok i have a 97 k1500 silverado z71 i use to get a misfier code all of the time i replaced cap rotor plugs wires and coil now i dosent do it till i tow my camper when i go up a grade i get a slight vibration then i feather the gas pedal and it goes away and resumes normal operation and sometimesw i get a misfire code can anyone help me with this problem thanks fellow truck owners