took the ute to holden a few weeks ago for its 15000K service. checked the engine oil life on engineering mode before hand and it was at 7%, so obviously needed changing. picked the car up and it was still at 7% but i thought it might take abit of driving for the computer to register the change. so its been two weeks and its now down to 3%. i'm no mechanic but i checked the dipstick and it looks like fairly new oil (i think) and it says on service report oil change. so why isnt it registering on the computer?