The above is why a tech needed to be involved. Somebody has to get his hands dirty and dirty from being in the right places even if the place turns out to not be the location where the problem lies. IOWs diagnosis is critical.Here is what the tech wrote when trying to fix the problem:
"Ran diagnostic codes in PCM stored P0642, P2174, TCM U1428, ABS C121C, U0401
Code active now is P0642. Measured 5V supply CKT F855 at TBODY 0.30V present currently. Ran diagnostic per code P0642. Tested and disconnected sensors on same circuit. No changes present. Didn't get to crank sensor yet. Engine hot and need to pull starter motor. After testing sensors and unplugging them, the voltage was back at 4.95V at TBODY. Plugged in all sensors while monitoring - no change. Voltage stayed at 4.95V normal. Cleared codes. Codes gone and engine runs normal. Attempted to road test. Vehicle acted up as pulling out oh shop while pressing accel pedal. Code set P1618, P2174. Performed PCM flash update per TSB 18-032-20. No changes to issue. Cleared codes; codes gone. Found at idle when bliping the throttle code resets and engine stumbles.
Possible internal accel pedal sensor fault. Performed harness wiggle tests; no changes. Need to replace pedal sensor and retest vehicle.
Installed new accel pedal sensor and performed relearn procedure. Cleared codes and road tested.
After about 5 miles of driving, the engine light came back on, right after a left turn and starting to accel. Checked 5V supply reading 4.95V running. Cannot get issue to reset in shop. Voltage hold steady; no glitches.
Installed new crank sensor. Cleared codes. Ran vehicle until hot. Tested operation. Performed harness wiggle tests; passed. Road test vehicle over 5 miles. Vehicle ran all normal as tested. Will let vehicle sit and retest again later to verify. Road test again over 5 miles. Vehicle is operating normal now; all ookay as driven."
I had no issue driving the car home (about 15 miles) but I haven't been able to drive since. May drive today and push it some to see what happens.
Thanks for the update.
Hope the issues are behind you.