2004 Grand Prix GT... Had a complete gasket job (both heads, intake, exhaust, etc.) done, oil changed, antifreeze changed... Less than 1,000 miles later today, all of a sudden the engine is knocking like crazy (speeds up with acceleration), idle fluctuating between 6-900 at stop, cutting off/stalling at stoplights, etc.. I can`t get a hold of the mechanic who worked on it - it`s too late on a Friday afternoon - but I have to imagine it`s not a coincidence - even he remarked at the time that everything else looked great? Help!
