Some observations from a guy who has made his living fighting fires for 25 yrs.

If you are going to carry only one extinguisher get a dry chem. (ABC) This will work on all of the fires in your car. Except for Metal fires.

ABC Dry chem extinguishers are filled with a powder that flows better than H2O. It goes EVERYWHERE. It is very corosive and WILL ruin all circuit boards it comes into contact with.

A CO2 extinguisher will work on many fires in you car. It is not rated for Calss A fires but will work if you have a large enough extinguisher and a small fire.

Cars that have fires that are of any size are almost always totaled by the insurance. Carry very good Compresensive Insurance, it is cheap it pays for fire loss. If you have a car fire you want the cash not the car.

Battery disconect is a good idea if the the fires is limited to just electrical arcing and nothing else, it will stop the fire from getting larger.

Car fires are the most under rated and some of the most dagerous fires we go to. Be very careful when fighting them. Do not breath the smoke it is full of many chemicals that will kill you or give you cancer.

If the fire is growing get everything out you can without breathing the smoke and getting burned, get away form the car ( at least 200 feet) and call the fire department, stay away from the car.

If the fire involves the interior of the car stay away, many of the new safety devices are powered by pyrotecnic devices. If they go off they WILL hurt you. They may discharge from an electrical only fire being as that is how they are normally triggered.

Many things that you would not think of will cause injury in a fire. Example, Lift struts on a hatch back can fail and go through the rear window and travel 150-200 feet. They have enough force to take your head off. really.

I carry very good insurance and no fire extinguisher. I have been thinking about starting to carry one though after I saw a car fire where soem folks were not able to get out and burned to death. This is most likely to happen after an accident. I like the looks for the drivers seat mounted extinguisher for this purpose.

A dry chem extinguisher would be a great start in saving your self if you could not get out. It is large enough to fight a fairly large fire, I have seen burn pits 20'x20' full of burning gasoline put out with smaller extinguishers. This was done by folks who were very good at running a fire extinguishers.