Hello, my name is Mark and I will try help you with this.
The first thing you need to do is connect a scan tool to see if any fault codes are logged.
This type of fault can be caused by a faulty accelerator pedal position sensor.
what scanning tool can you suggest Mark? So many on the blessed market I'm confused. By the way, I have 4 vehicles, Nissan Trooper - Nissan Micra - BMW 250 series and of course, this Astra. At least, I work on them all! Thanks. Pete
I would recommend the Autel Maxidas.