I live in Florida - St. Pete area - park outside -windows up and I have Spiders! 1/2 - 1" across - I’ve nearly wrecked the car a couple of times, Help me - How can I get them out!
Remember that spiders–like all living things–need a food source, and if you remove the food source, the spiders will leave or will die. How do you remove their food source, namely small insects? Well, borax is effective for ridding basements of spiders by killing their food source, so this could work in cars also.
Take an empty tuna fish can (or two). Rinse and dry well. Place about 1/2 inch of Twenty Mule Team Borax (available in the laundry product section of large supermarkets) in the can. Sprinkle the top surface of the borax generously with sugar. Place one of these cans underneath the driver’s seat or the passenger seat–whatever is relatively easy for you to access. Perhaps you might place another can in the trunk, for good measure.
The unseen insects on which the spiders are feeding will eat some sugar, and in the process, will also ingest some borax. The insects will die, and shortly thereafter, the spiders will either leave or will die from lack of insects to dine on.
Alternatively, after a few weeks of the borax treatment, if you find that the spiders are still a problem, there are specialized aerosol sprays for killing spiders. I know that Lowe’s carries a product of this nature. However, since all products of this type are toxic, I would recommend that you use something like this–in a confined space like a car–only as a last resort.
I’d try to capture one and bring it to your state’s Department of Agriculture office for identification and recommendations. They can tell you what it eats, where it nests, how and how much it reproduces, and how to get rid of it safely.
I’ve used this service in my state and they really are amazing. They told us exactly where to find the nests of the bugs we were seeing and how to eradicate them without poisons.
Yes, the folks at the Agricultural Extension Service are incredibly helpful for anything relating to insects, spiders, soil problems, or virtually anything else that is a problem in your garden, or perhaps even in your house.
Recently, I captured a couple of really weird-looking bugs in my garage, and one in my bedroom, and they identified it as a Stink Bug of the type that apparently came into this country from Asia a few years ago. They are spreading rapidly, but so far, there is no recommended insecticide for use in the house to combat these things.
The good news is that they move so slowly that they are easy to capture. The bad news is that if you crush one while in the act of catching it, the smell is really bad. All of this info was provided gratis by the nice folks at the NJ Ag. Extension Service/Cook College/Rutgers University.
I watched exterminators this weekend, They had a very safe spray for use around kids an animals that would kill the spiders. Their suggestion for keeping the spiders away was to eliminate all exterior light sources that attract bugs, the spiders food, window shades, etc… It seems so simple. Take a look near your car at night identify light sources that attract bugs near your car and eliminate them. The guy they helped was infested with black and brown widow spiders so count your blessings.
I’ve had three spyders (one Alfa and two Fiats) and the were all great cars! Cheap to buy, easy to fix and fun to drive! Looking forward to Alfa and Fiat returning to the good old US of A. No worse than what Detroit has been peddling as cars for the past many years.
Twotone
Oh, that post that is cracking me up! LOL! 
Spyders/spiders… hahaha! I get it. Hope you have no spiders in your Spyders!
Connect a hose to your exhaust pipe and the other end through a partially opened window and seal off the rest of that window with duct tape. Start the engine - GET OUT OF THE CAR - and let the fumes fill the car for 20 minutes. Then hold your breath, open the driver side door, get in, shut the engine off - GET OUT OFF THE CAR - open up all the other doors and air the car out for 20 minutes. Repeat if necessary.