Have a 2008 Chev 3500 van, 296,000 mi, starter not disengaging on some trys. I thought the culprit was the starter, but changed on Thursday, 12/1, and at second startup it stuck again. Could it be the ignition switch? If possibly the switch, how can I check/remove/replace? At this point, since I have to be ready to roll at any time of day, once started I just leave it running for my 12-15 hour shift. Thanks in advance.

 

Welcome to the forum. The starter on yours (the starter solenoid, actually) is powered by the CRANK relay in the underhood fuse block. Turning the key to START causes the ignition switch to send a voltage signal to the BCM which in turn causes the ECM to energize the aforementioned CRANK relay until the engine starts. There's also a timer to cut it short when the engine doesn't start. On my Malibu, I just turn the key to START and then release it immediately and wait for it to start itself. Try it and let us know what your vehicle does.

 

Well, it started correctly more often on Sunday, after your advice, but several times the starter continued to crank. I just turned off the key and tried again and usually by the third or fourth time it caught and started just fine.

 

It sounds like the ignition switch is not releasing cleanly from START. Proving it would be nontrivial for a typical DIYer, however. Consider taking it in for service.