Hello and welcome! :)
I work at a Buick dealer and work on a LOT of Rendezvous. Yours is not running warm enough? Has the dealer driven the vehicle with a scan tool installed and read [u:1ae6651b02]actual[/u:1ae6651b02] temperature?
Let's leave the gas mileage issue alone at first till we determine that your engine is running at the right temperature. :Wink:
winter blends of gasoline can affect mileage depending what state you live in, blends can vary greatly. What area of the country are you located in?
Tuesday, December 12th, 2006 AT 9:57 PM