$3000 is a lot. I get that, my wife and I have been where you are. But it’s a lot cheaper than a new car. What concerns me is the “knocking noise,” which I suspect is caused by low oil and could easily lead to engine damage. Whatever you do, make a commitment to take care of your car. If you treated a dog or cat the way you do your Camry it would be dead by now. If you do decide to replace your current vehicle, you might be able to find a used Hyundai or Kia for $10000 or so with some warranty left.