You will probably need to bite the bullet and purchase a new battery. We have a 2003 Toyota 4Runner and I just replaced the original battery this fall. The original battery still cranked the car just fine, but on measuring the voltage with the car off, the battery was as 12.2 volts. I decided not to take a chance on a seven year old battery. Also, since the 4Runner has an automatic transmission, I can’t jack it up and put a rope around one wheel to start it as suggested by a Puzzler.