Pontiac Grand Prix 2006 random ignition misfire; replaced plugs, wires, #2 and #5 coil; still not working; cruise control stopped working at the same time the misfire started; also getting muffled noise or nock with rough idle and acceleration; also very poor gas millage.
After replacing the ignition control module the problem with random misfire was fixed and the cruise control came back on line again; problems solved.
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