I have done a complete tune up on my 2005 chevy silverado
and my check engine light is still on can someone please tell me why and how do i turn it off or what else could be wrong:banghead:

The check engine light goes on because your computer is reading something out of specs from a sensor somewhere. You need to find out what sensor is reading what first. A "tune up" most likely isn't going to fix anything. However getting the tune up definantly didn't hurt anything. Anyways, you need to find out what code your getting and go from there.

If you have an Autozone close by they will scan your computer for free. Find out what the trouble code is. It should tell you what the problem is, but if you have any questions repost here and you should get a quick answer.

Yup get the code read and post it here, then we can help. :)

The Dealer (mechanic) said to disconnect the battery or Batteries.. Touch the + and - together (this clears the computer) reconnect the terminals and start the vehicle.. It will re-learn and if the problem does not exist no code will display.

The Dealer (mechanic) said to disconnect the battery or Batteries.. Touch the + and - together (this clears the computer) reconnect the terminals and start the vehicle.. It will re-learn and if the problem does not exist no code will display.

That is not a fix, bandaid. There is a reason the CL came on in the first place.