Is there a word for the feeling of wanting something material?

Yes: covetous:

feeling or showing a very strong desire for something that you do not have and especially for something that belongs to someone else [M-W]

If you want a noun, covetousness. But here is one case where the verb does most nicely: “I covet that.”

If you can denominate sexual desire with the term lust, I anticipate no insuperable problem with the scriptural baggage of covet.

Somewhat obvious suggestion, but how about materialistic?

1) The theory or attitude that physical well-being and worldly possessions constitute the greatest good and highest value in life.

2) Concern for possessions or material wealth and physical comfort, especially to the exclusion of spiritual or intellectual pursuits.

thefreedictionary.com

Being covetous often implies what you want belongs to someone else (which could even include your neighbour's wife as well as his ass).

To my ear, acquisitiveness might simply imply a tendency to accumulate possessions (by not discarding things you no longer need, as well as being keen to acquire them in the first place).

So I suggest:

avarice - extreme greed for wealth or material gain

Caveat emptor: this answer, offered with levity, is directed specifically toward the example of the desire felt toward an automobile, rather than toward material objects in general, which I believe is a manifestation of MATERIALISM.

Well, if this was a simple one to one proposition, like hunger is want of food, and lust want of sex, then perhaps you could say that the desire for a car was want of mobility, i.e., immobility, or the feeling of being ... stuck i.e., blocked, wedged, or jammed. (links are to Merriam-Webster online)

Unfortunately, I think that this want is less directly tied to the issue of mobility in general, and is instead, highly specific, often directed toward a certain car, one particular car out of many cars (I know. I've seen the look.). So, perhaps the best way to describe this ... desire, is just to call it what it obviously is: lust. In this case, Car Lust. ;-)

Car Lust: extreme desire of an automobile. Usually happens after driving an awesome car, usually a friend’s or a rental. “Dudes, I have serious car lust after driving that 1969 corvette!”

(For definitions of "Car Lust," see definithing.com & the Urban Dictionary)

Exhibit A