OK I have researched and cant find a post on this one. When I hook my code reader up to the plug in my blazer it does not do anything, I know the code reader is good I just finished using it on my sons car.
2 questions:
1. how can I track this down.
2. if not can I have a shop hook it up to something to give me a reading or diagnose the issue, I am getting really bad gas mileage and it is running a little ruff. I put new plugs wires in it a month or so ago.
Thanks for any help
Bryan

 

check for blown fuses...

 

its usually a cigarette or accessory fuse of some sort.

 

Thanks I would have never found that one guess you r never to old to learn. u guys rock