as everen said there is no reflection, just do as we do in brazil, put a WHITE plane (as vray works with realistic "enviroment"(i dunno the right word) if u put a red plane it will render red reflection) where u want the reflection(the position depends on the position of the camera)
When you press M and go to the car materials slot, you'll see one slot called(most of times) "Skin", then click on it, scroll down to maps, go to difuse, click on "none", choose bitmap, select your skin and render
maybe try to decrease the "multiplier" of your HDRI or try to decrease your GI Enviroment Reflection/Refraction from 1 to 0.7, 0.8, 0.5, just play with the settings for it to seems more "matte" (realistic). If you have photoshop(probably yes) try to tweak your render. =]
EDIT: Sorry dude, I don't know if you'll get anoied with me but I had to give it a try ^^
I tweak just a little with photoshop and for me it seems better
(it is just a little modify, but open one in one window and another in another window and compare.)
the car is bright and the background image is dark, but its very good anyway ^^
maybe u're using "affect background image" in color mapping. try to turn it off and see if it works
If you want to do what I'm thinking just press M, click on the button circled in the image(attachment), and with it click over the object you want the material
I agree with pacesetter, you need to change your rim material(the model is good) and windows material.
I attached my glass material for studio scene, but I think it will work for outdoor scene too. Take a look.
The middle of part that touches the road of the rear tyre has texture.
Tyres have too much reflections.
Textures have so much bump.
Wheel doesn't fit with this car.
I was trying to fix my FZR windows and I was that all vertexes aren't alligned, they're flying away, so you need to weld them manually, applying smoothing groups won't help.