I have been rebuilding a 2001 Camaro Z28 SS SLP with a 5.7 V8. After I finished the work I drove it for awhile. It developed a back main seal oil leak after the first oil change. Pulled the automatic and changed Rear Main and rear plate gasket and fixed that. Then on a very cold night in Nebraska (10°) my wife and I decided to take the car to another town for dinner and a movie. We got about 15 miles out and all of a sudden the car started missing, stumbling, backfiring and then just quit. After having it towed home, I changed the battery (a nite with flashers on in 10° killed the battery) and the car restarted. However shortly there after it did the same thing in the driveway. Occasionally it would run. This was going on during the oil seal change. Then it quit again several blocks from home and another tow.... Lots of trouble shooting later I surmised the Crank position sensor was bad so I changed. Once again it started but soon stopped. More trouble shooting, then back probing sensor wiring and other computer pins, I found the computer heatsink was sitting about 10V off ground. The sensor input pins were only about 9V and the vehicle would not start. Tracing the source of the problem, I found the computer ground terminal on the back of the driver side head was loose and causing an intermittent condition. Of course, this ground served the ignition and injectors as well as the sensor. After tightening this down, the car now runs perfectly. Lesson learned..... Check the grounds first.... Thought I would share it.

 

Thanks, Murphy at work.