hey scotty i have a hyundai veloster 2013 and there was smoke coming out from tailpipe and i noticed oil on top of the valve cover so last week i replaced the valve cover gasket but theres still smoke coming out from the tailpipe also i noticed that when i start the engine the rmps go up and down but only for a few seconds

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engine is flat worn internally, smoke coming out the back is burning oil and or coolant. Do my video "how to tell if your head gasket is blown" to see if it's that