dam sorry to hear this.. my auto teacher was a rep for the city to do follow up on the lemon law.. The car does not have to be under warrantie.. And if it is constant problem one after another that you can prove that it has nothing to do with the way you drive then you got a case.. LIke in your case iwth 4 tannys and such.. Talk to the Better Business Bureu and see what they suggest, they should give you some number.
Good Luck.
tony