My 95 jimmy is running rough, shaky at idle. I had a guy hook up the scanner and my computer could not hook up. Could not find problem that way. Could it be a sensor?

Theirs a wire behind the computer unplug and restart the vehicle if it runs good you need a distributer common problem

Common for the EGR valve to get dirty with carbon and causing it to stick open. Start with the simple and clean your EGR valve and throttle body, if the EGR valve is to far gone to be cleaned. Your going to have to replace it,you can use Deep Dreep made by Seafome and would be a good idea also to give your Jimmy a Seafome treatment.
Use two cans and follow the instructions on the can and thins should bring life back to your engine.
Thank you for using fixya, and be safe.
http://www.seafoamsales.com/ http://gmcowners.com/gmc-forum/showthread.php?t=13770

Hi guy is that a Vtec engine seem like EGR valve stuck open