D.W.
We just found ants in our boys bedroom window, which is next to their beds. We used Raid household bug spray (we already had it but had never used it around the kids). We sprayed it while the kids were downstairs eating dinner and opened the window. By the time they went to bed a few hours later the ants where done and so was the smell. We sprayed again a few days later to make sure there gone for good. so you might be able to use that in the car. Good luck. Seeing you post gets me thinking my own car and all of crumbs I have!