Prius won't run when given gas/go in park.Engine always has ran rough at start up.

Unfortunately it sounds like you're coming up on the generation 3 lot of work and maintenance issues 3,500 to $6,000 is not unheard of so if you don't have that kind of money it may be time to start thinking about less gas mileage and more go like a Yaris Corolla Chevrolet Aveo if you must something but you'll need to get it around to a few places and a few mechanics and see what everybody has to say You've got enough reading to keep you busy for about 2 months unless you're a very fast reader and comprehend very well because this stuff all goes round and round and long circles and stretches to far ends of the globe seriously it's a lot of reading It's a lot of round and round and a lot of numbers and lot of ifs and if you don't have time for all these antics and the ifs you may want to bow out now and get yourself a car that you personally can deal with because in my eyes this is not it and for a girl too not saying that girls can't do anything just I wouldn't put my daughter in this vehicle even when it was a lot younger and before the problems began and she even knows it. Has nothing to do with that unfortunately I don't know what happened You like the way the car looked doesn't really matter at this point many people have been in your shoes and many people have been disappointed and as many people and more have been very happy so it's a real toss-up in this day and age you can't really believe everything you read and see because well it's a lot of things going on. And good luck with your choices there will be some of that involved unfortunately

 

How many miles on your Prius?

Which warning lights are illuminated on the dash?

I am guessing that the scan tool that you are using can not read all the trouble codes that your car has. I would advise you to purchase a better scan tool. Read this thead:https://priuschat.com/index.php?posts/3290690
Choose a scan tool that can read all the trouble codes (look at the data column, they are the ones that say "All"). The Autel AP200 is a good choice.

 

put her up on a lift and check the O2 sensors around the cat