Yesterday my 2013 C-Max would not start. I jumped it and attributed it to lift gate not closed all the way. As I attempted to drive the vehicle, it would not respond to depressing the accelerator but would self accelerate to 35mph. When I applied the brakes it would respond. I drove it 43 miles that way with a lot of stop and go traffic to home to troubleshoot. Found my primary battery at 8.4 VDC. Put my portable jumper across my primary battery and was able to drive normally to purchase a new battery. Noticed old battery manufacturing date was 1/15. Yes, 9.5 years old. A new record for me.