Knocking sound coming from plenum
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Knocking sound coming from plenum
Long story short, I was on my way to work, in cruise control.. car lost power and started knocking. Pulled over and had car towed home. Sound appeared to be coming from intake plenum area. Tested with stethoscope and it definitely wasn't coming from bottom end. Drained oil and pulled filter, no metal in oil. Pulled upper and lower plenum and valve covers, notices two intake valves not closing all the way. What would cause this? What should I do to remedy this? Please help.
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