Well if that was part of the "deal" to have it fixed then they need to do their part and have it fixed! So far your doing everything right, do not I repeat do not take that car until it is fixed or what your contract was agreed on. Be aggressive their a "dealer" they need to live up on the deal that was made. If they get aggressive back and try to use that tactic on you(which they do often and is used to intimidate customers so they'll say yes to the deal) keep your guard up. If they do yell then yell back and tell them "is this how you treat all your customers! then reiterate your situation."If they don't then they are not following the contract. Which in result cancels out the contract and your done. Go somewhere else that can satisfy your needs.