my daughter owns an 01 vauxhall vectra 1800 petrol 5 door, she is getting an intermittent fault where she loses acceleration. If she turns the engine off and restarts it normally fixes itself. we have had it in a garage and various parts have been changed including the throttle senders (motors)
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix cars.