Could do with some of your worldy knowledge and expertise. I have got a '93 Corsa GSI (if you have got a copy of March '03 Total Vauxhall, it is the cover car) with a Mantzel power box. The car seems to be a bit hesitate either when pulling off or when you are just going along. Having not owned the car before the power box went on, or having owned a car with a power box before i dont know what is normal and what isn't!!