car dealer theme

I am trying to alter the images on the front page that go with “city car sedan coupe” etc. I have found where to add new images in the car file in the template but where do I find the code to use the replacement image?. eg one of the files is called 1.png and I have deleted that file and added a new png image file but I need to find the part in the program where it says to use 1.png and add my new image in its place