I would: change all spark plugs, change all ignition wires, change all the coil packs and the ignition module. I would then have the suspension examined by well known shop and make any changes that they recommend. The Grand Prix is not a sport handling car; it's a road car that looks and feels great going fast in a straight line. My gp was getting 29/22 mpg hwy/city and it averaged about 25 mpg with about 80% freeway driving. I absolutely love my car even now when there is a miss on my #5 cylinder and my mpgs have tanked a bit (mostly due to me not putting it on the freeway). It now has 201K miles and I know a guy that has 2 that have 260K miles or better and he still drives the freeway with them....


Quote Originally Posted by 5am View Post
seems to get pretty bad gas mileage along with not seeming to roll as well as a car should. maybe it needs an alignment. hard to tell im not that smart. tires don't make any funny noise though .

untechnically speaking , my previous car (Subaru svx ) just seemed to want to roll or move easier , its not because of weight difference they are both about 3500lbs. maybe its how the transmission is geared . hard to tell if wheel bearings need to be replaced . the display does keep showing (service ABS ) and (service traction control). I think the dealership I bought it from needs to pay me some money back lol.