Resurrecting an old thread. I have a 94 Z71 190k. 2nd owner bought it with 120k. I have replaced the alternator, fuel pump, changed tranny fluid, changed rear diff fluid, replaced shocks, 1 ball joint, and front axles. Truck is used for hauling and towing. Added flowmaster, airraid, throttle body spacer, plugs, wires, and motorvation stage 2 chip. A few months ago the truck started running rough going on for weeks. I couldn't find anything causing it. Finally it died for 45 minutes at a stop light and came back to life on its own. When I got home I removed and reseated the motorvation chip and it has run fine ever since. It is cooler due to the winter but I am not sure if it was the heat or the chip. Has anyone had a similiar issue? I love this truck and plan on keeping it for a long time. It is paid for and does everything I want it to do.