Canyon 'Content Theft Deterrent' Problems Starting

I have a 2004 GMC Canyon Pickup with the 5 spd and 4cyl engine. It has 53xxx miles on it. Recently, when I push-in on the clutch and turn the ignition to start, NOTHING happens until I release the key from the start position. The truck then immediately begins to and does start. This does not happen every time I start it. But when it does do this, a warning light comes on and stays on that (according to the Owner's Manual), is for the 'Content Theft Deterrent System' which this truck does NOT have. I have NO Remote Keyless Entry System.
The truck runs fine after starting it at the times this light stays on. When I turn the truck off and restart it, this may or may not occur again.
Shortly before this problem began, I began getting the message ... Change Oil...across the dash display. That display will continue until I briefly push the Odometer/Trip button and then it will not come on again until I stop and restart the truck. I had the oil changed less than 600 miles ago. Are these related?

Please Help If Y'All Can.
Thanks, Bigindin.

I have a 2004 GMC Canyon Pickup with the 5 spd and 4cyl engine. It has 53xxx miles on it. Recently, when I push-in on the clutch and turn the ignition to start, NOTHING happens until I release the key from the start position. The truck then immediately begins to and does start. This does not happen every time I start it. But when it does do this, a warning light comes on and stays on that (according to the Owner's Manual), is for the 'Content Theft Deterrent System' which this truck does NOT have. I have NO Remote Keyless Entry System.
The truck runs fine after starting it at the times this light stays on. When I turn the truck off and restart it, this may or may not occur again.
Shortly before this problem began, I began getting the message ... Change Oil...across the dash display. That display will continue until I briefly push the Odometer/Trip button and then it will not come on again until I stop and restart the truck. I had the oil changed less than 600 miles ago. Are these related?



Please Help If Y'All Can.
Thanks, Bigindin.

Welcome to your first post on AF.

The change oil message just may need the reset procedure..
look in owners manual.
The starting may be a ign switch problem.
You can get a All Data DIY sub and look at the wiring digram and see if the ign switch is switching the proper signal to starter/relay or starter in the start position.
http://www.alldata.com/products/diy/index.html
If it kicks in when you back off of switch it may be a bad switch or need adjustment.
If you can not find the problem run it by the dealer and get them to have a look at it.
It may have a recall or tsb's { a known problem on it}
Good luck and let us know how it goes.
MT

Thank You Very Much Sir, for your thorough and understandable reply.
Bigindin.