You may have an intake manifold gasket that started leaking and blew wide open. Essentially it causes a vacuum leak in this case (if this is what happened) giving the high idle. Sometimes you can have an oil or coolant consumption problem of coolant infiltrating the crankcase as well. Granted this is more typical of newer 3.4s than yours. Check for a massive vacuum leak regardless to start of with.
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Friday, October 26th, 2007 AT 7:36 AM