Vauxhall Zafira 03

[minky moo]

my old run about car that is mainly used to take the dog has developed a fault in that it is like driving a bucking bronco, the garage says there is nothing wrong with it and it showed just below 10 on the rev counter but now the counter goes up and down far exceeding the 10 as you drive, otherwise it is a brilliant old car, have any of you experienced car heads got any advice - it would be greatly appreciated. Thank you