I stumbled on this effect "by accident."

Required the
Impressionist plugin.
1. Duplicate Background.
2. Apply Impressionist Pencil Sketch: Detailed Mono
3. Change layer blend mode from Normal to Lighten.
4. Duplicate Background again, drag to top of layer stack.
5. Apply Impressionst Crayon: Short choppy strokes. This "chops up" the image somewhat.
6. Apply Impressionst Charcoal: Default.
7. Change layer blend mode from Normal to Darken.
I didn't like the parking stall stripe. Should have cloned over it before starting.
8. Create a new layer at the top of the layer stack.
9. Select Clone tool. Turn on options
Aligned and i]Use all layers[/i]. Set brush opacity to about 80%, flow to 60%.
10. Clone out the stripe. Note: Doing this cloning on a separate layer = ultimate flexibility. Start over, add a layer mask, etc.
Car shadow was too dark.
11. Add a Levels adjustment layer at the top of the layer stack.
12. Drag the middle slider to the left until you're okay with the car shadow tone. (My setting: 1.81. Use your own judgment.) Don't worry that everything is washed out.
13. Ctrl + I to invert the Adjustment Layer's mask (turns it black).
14. Select Brush tool. Turn on Airbrush option. Opacity ~ 60%; Flow ~ 60%.
15. Set foreground color to white by pressing D and X keys.
16. Place brush over image and right-click, bringing up the Brushes Palette. Choose a Soft Round brush (makes no difference which one) and make the size 50-70 pixels using the slider at the top.
17. Airbrush shadow area to lighten it. The longer you airbrush, the lighter it will become.
I still thought the shadow was a bit dark, so I set the blend mode of the Levels layer to Screen which, for me, did the trick.
At this point you might want to restore some detail to the car. Optionally, duplicate the Background, drag the duplicate to the top of the layer stack, set the layer blend mode to Luminosity, Layer > Add Layer Mask > Hide all (add a hide all layer mask) and airbrush white in areas of the image where you want to restore detail, e.g., around the headlights or grill or wherever.
~Danny~