If you really believe you are right then stick to your guns. If the normal dialogue doesn't get you anywhere then make sure you keep the phone records, photos, video, etc. If you want to really want to give the dealer and Vauxhall something to think about, then start a website with your complaint. As soon the search results start showing the dealer name with a problems customer and car, they will think twice about being difficult. A one page website with photos, facts with links to YouTube, Twitter and Facebook should cost not more than £100 to set up. Also get hold of motorcodes, search it