My V8 ST check engine light is back on. Got bigger problems now. I was pulling a trailer this weekend going up a steep incline running pretty hard and something happened. Started running rough, some kind of noise, smoke and CEL light flashing and lost power (limp mode I assume). I pulled over, checked fluids and did a visual inspection. Couldn't find anything, started back up, engine noise under load but not at idle. Drove it on home very easily. Pulled CEL code, P0301. Did a compression test and cylinder 1 at 30, two others at 120. So I assume a valve, ring, gasket or piston has failed. Any ideas how to tell what happened for sure?