I calculated my gas mileage on my 04 envoy and its 12.8 miles per gallon. Is that normal and is there any way to improve? I have 155,000 miles and the 4.2 I6 engine.
Ok not sure if I am in the right forum but here it goes... I have an 03 Trailblazer LT EXT 118,000 miles... it has been idling rough for a few months..the hubby changed the spark plugs and found oil on the threads...getting really bad gas mileage...oil pressure is higher, ranging between 40-60...