Alright guys well I'm new to this form and my names Bradlee. So iv had this 02 duramax for awhile now and it was running then I replaced the passenger side injectors and connected it all back up and I tried jumping it with 2 trucks because I had no batterys in it and it would turn over kind of weak so I put a new starter in and now as soon as I go to plug a battery up it'll spark then start engaging my new starter... So I exchanged that starter for another and same thing happens. I'm clueless please help.

 

Also I figured maybe the little wire and the big wire that goes to the starter might be touching so I cut the little one off and the starter still gets power. I was thinking the bigger wire that goes from batterys to starter might be causing it but how. All I did was replace the starter

 

Anyone think they could help?

 

Sounds like your starter solenoid is staying engaged. Several possibilities as to why. Never touched the starter on my LB7 so I may get this a little wrong- but should be like all other GM starters I would think.

The solenoid has 12V from the batts full time. The start wire from the ignition (used to be marked "S" on the solenoid), is what activates the magnet in the solenoid and engages the starter. If you have 12V on that "start" wire full time, that could do it.

A short between the start wire and the 12V supply from the battery could also do this.