I have a 2002 with 186,000 miles. It is showing its age. The main battery was having problems so I pulled it out and found 5 batteries with problems and replaced those. When I tried to start the car it took 4 attempts but eventually started. After a week I let my son take it and it again had problems...revving the engine, loss of power. He pulled it over turned it off and it has not started again. I had the 12V battery tested and it only has 200 cranking amps. Could a weak 12V battery cause these problems. The catalytic converter is going out on this car and I don't want to keep putting money into this car if it is time to give up. Any help would be appreciated.
A bad 12V will not usually cause a failure during driving. The old GS battery was rated at 272 CCA, so if yours tests at 200, that's plenty. It is possible that something happened during reassembly, such as a loose HV connection or broken sense wire, that is causing the problem. If you can get the diagnostic codes read and post them here, we can maybe offer more help. The catalytic converter is a huge PITA if you live in California, as pretty much only a Toyota cat is allowed as a replacement. They do make cheaper aftermarket ones, but they are illegal to sell or install in California.
