It all depends on how much you want to keep the vehicle. If it is not important to you, junk it. If it is and you can afford to keep it, invest the money or buy one that doesn't needs as much work. I was in a similar situation. Mini van needed a lot of work...blown head gaskets, rebuilt transmission and new sensors for smog to pass. I have spent more on it than I paid but I wasn't going to throw the money out the window and start again. I bought the vehicle so that I can travel with my bikes so for all that I have spent, it has paid off for many nice rides.