The information can't be removed because it is accurate. By definition, a short sale doesn't pay off the loan in full, so there's a leftover balance. It was probably charged off by the original lender because the lender had little, if any, hope that you'd be able to pay it. That doesn't mean your debt has disappeared. You still have a balance due, so it is still an active account. The new company you mention probably bought the loan from your original lender at a discount, and they will now attempt to collect.
Before dealing with this second company, you should check your 2009 tax return and see if the original mortgage lender issued you a Form 1099-C for a forgiven loan. If the lender did issue you one, you can use this to fend off any collection attempts. If the lender did not, then you still owe the cash.
In my experience, first mortgages are almost always forgiven in a foreclosure. Second mortgages are not unless your state prevents collection of second mortgages. This is sometimes the case if they were part of the original purchase of the property. Many people who decided to allow their homes to be foreclosed on or sold in a short sale are now facing the consequences of unpaid balances on second mortgages.
My guess is that your second mortgage is still active and collectible. I recommend you focus on the likely possibility of a concerted effort to collect on your second mortgage balance and develop a plan for repayment.
Typically, the new creditor will start with a letter, then call you on the phone, and then take you to court seeking a deficiency judgment. If and when this happens, don't ignore them. You may be able to settle this account for much less than the total amount owed.
Also, make sure to review your financial situation and determine what you can realistically afford to pay on this debt. Once you do that, you'll know what you can offer when the creditor calls. If you can't come to an agreement, you may need to investigate your legal options with an attorney.
As far as your car loan, I suggest that you be upfront with any potential lender. Explain the situation behind your short sale, and be ready to explain why it won't happen again. If you didn't default on your last car loan during this process, point that out. Car lenders like to know that you have a record of paying them first in a pinch.
If you can't get a loan you can afford, you may need to postpone buying a car or purchase a less expensive car.