Thermostat and exhaust both sorted but the car is running like pooh. Below 3k revs it drives like my OH's Polo. Also I only managed to get 24 mpg on the motorway. What are the possible causes of this? I'm too lazy to search because it's my birthday today and I went out last night and I'm very hungover and can't search in my retarded state of mind. And because it's my birthday you can provide me with answers, as a present.