There are no practical alternatives to burning the vehicle, unless you are able to positively identify the arachnid as among those whose venom is non-fatal, at least to the degree that it won't incapacitate you while driving in heavy traffic ... Meanwhile, you risk your own life, as well as your passengers' and other motorists, while driving around with this creature lurking, probably under the dashboard, ready at any moment to leap out and climb up your leg and nip you in your most sensitive regions, causing you intense pain and to abandon control of your vehicle and careen out of control into oncoming traffic, with schoolbuses carrying orphaned children to Sunday School, and OMG!!!
Well, you probably get the point ...