My car was throwing check engine light and running really bad. I run the codes and had several especially PCM codes. I downloaded Hypertech and uploaded stock program. Issue resolved for a few days. I noticed the voltage was low 13 vs 14.2 blammo the check engine light and lousy performance. Uploaded the hypertech and no issues.
Next morning car was dead no lights nothing. It turns out the ground cable had worked itself lose???? and the intermitten voltage was the source of all the shenegans. Just sharing my parapsycho discoveries. It was real close to going into the shop and was a very simple source of difficulty. these wonderful cars are very electrically dependant

No doubt. I had something similar happen to me but it was a short circuit with a lighting harness I installed (my own dumb mistake). Lukily I was aware enough to figure out that I had recently installed something and it was probably to blame for the CEL and rough engine. It sure gave my heart a jump when the engine started acting like it was not getting any fuel before I came to my senses and made the assumption it was the wiring work I had just done.

Congrats on it being a simple fix.