It's just a guess, but it seems that the electronic sensors in these cars are rather sensitive, and that older batteries have caused certain problems like alarms going off for no reason, etc. Also, at 6 years old a battery can die without warning and leave you stranded somewhere. My wife's minivan battery died without warning last month at 6 years. That's why I'm replacing my roadster battery before heading down to St. Louis for CAA.

I don't know if a dirty throttle body might cause driveablity symptoms like you are seeing, but again it may be worth a try to clean it out. I've seen posts on how to do that on the forum. I'd also pour in a 20 ounce bottle of Chevron Techron fuel injector cleaner right before your next fill-up and then run that tank down low. Techron is the best cleaner I've used and does a great job of getting deposits off the injectors.

Best wishes on solving the problem.