engine shakes and misses at idle what would cause this

yes engine light is on it has 2 codes p0128, p0300

not sure on 128 will ck at work tomorrow but 300 is random misfire

not coil pack had it checked

Did you inspect the spark plugs to see if there was any differences between cylinders?Pull the valve cover and check your pushrods and rocker arms.If a rocker arm popped off thats an easy one to spot.if none are off then slowly crankthe engine over by hand and watch what each pushrod and rocker are doing. If a valves bent .....never mind probably wrong tree...