Accelerator Pedal Sensor problems of the 2005 Subaru Forester

While driving, the car experienced: -loss in power (stuttered a couple times), then completely stalled -we had to coast it to the side of the road -a few hours later we tried starting it again and it ran fine -immediately before the problem, the car had been driven for ~15 minutes with no issues, there was no rain, it was a dry day, no other potential causes to be noticed -this exact issue occurred about a year ago and the problem could not be identified, it has been driving fine ever since, except in the winter the idle will sometimes fluctuate (unsure if this is related) this stall condition could be very dangerous if it occurs on the highway, at an intersection, etc. It produced a check engine light and code p2138 when read with a obdii scanner. Unfortunately the problem was intermittent and was not able to be repeated. The factory troubleshooting procedure was followed to determine if it was a problem with the pedal sensor, the harness, or the engine control module. All passed the tests. So we are left with a potentially dangerous electrical issue that can't be verified to be fixed because it can't be recreated.