Open up your image of the car you want to transform into your knight rider wallpaper, i shall be using this picture of the audi rs8.
Firstly lets remove the number plate, select the polygonal lasso tool and make a selection like this.
Copy and paste the selection to a new layer and move it up over the number plate, you may need to duplicate it more than once to cover it. You should then have something like this.
Merge the new grill with the main image so you left with one layer. Duplicate your main image then goto "filter > stylize > glowing edges" use these settings,
Edge width: 1
Edge brightness: 20
Smoothness: 15
Also set the layer blending mode to "Linear Dodge" and press "ctrl + u" and colorize the image red. You should have something like this.
Duplicate your main image again but drag it to the top so its on top of everything in the layers window so far. Set layer blending mode to "Linear Burn" and opacity t0 30%, then goto "filter > blur > guassian blur" blur by 2 pixels. You should be left with this.
Now create a new layer above the rest, select the colors #e49d3e and #8b5521 and goto "filter > render > clouds". Now select the rubber and remove the clouds from the main detail of the picture.
Now set the layer opacity to 60% and blending mode the "color dodge" you should have something like this.
Now zoom in on the grill and create a couple of red squares.
Add an outerglow using the settings below.
Create 3 cirlces using the color #f8f9d7 and place them in the middle of the grill. Also guassian blur them by 2pixels.
Now select the paint brush tool, then select the assorted brushes, then select the crosshatch brush.
Add 3 crosshatchs on your 3 circles. Your image should now look like this.
Now add some text to your image.
Now select the rectangular marquee tool and create some squares like this.
When your done merge all your squares as one then click your layer whilst hold the CTRL key on the keyboard to make a selection. Select a light red color and a dark red color as your background and forground and drag a gradient over your squares (Or just add a gradient overlay).
Now add a outerglow & stroke using these settings.
You should have something similar to this.
Add a layer mask to your squares and set opacity to 50% and your done.
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