Disputed accounts are often removed during the dispute process, it should return. The cannot actually remove the account permanently without your concent (even then technically they cannot). The FCPA states that if an account is reported, the company is required to continue reporting it.
Credit things can take time. Welcome to the forum.
Welcome to the myFICO forums!
The first question is, did you have late payments? Are you purchasing the car from a "buy here, pay here" dealership?