Driving, the car will slow or stop as if no power. At first, I could just turn off the car and wait a few minutes and it would be fine. Sometimes the car has no issue for over 60 - 100 km. and then it will begin to act up again.

Opel mechanic did diagnostic and says it is a gas pedal issue at a cost of nearly 500,00 euro to fix. Is there a simple solution? A less expensive solution?