My wife has a 2010 Impala that wont stop cranking over until you unhook the battery. As soon as you turn the key to accessory it starts cranking and doesn't start. I pulled the starter relay to run codes and I'm getting a fuel pump code. Everything was working fine 20 minutes before this happened. I put a new ignition switch in it and tried starting it without the tumbler in it and it still does it. I pulled the starter and bench tested it and it seems to work fine. I have been researching it and all I can come up with is welded contacts in the starter or stuck tumbler. I'm starting to think it could be the computer because its giving a fuel pump code. If you push the valve the fuel has lots of pressure. Any input would be appreciated. I'm about to put in a new starter but I really don't think its going to help.