OK I need some help, I have a 2005 Chevy Cobalt with the 2,2L. I recently did an oil change 3 weeks ago and have been keeping an eye on the oil and i checked it the other day and noticed it was low yet again. So i changed the oil again after i noticed that and there was only 3.5 quarts of oil in the car. Has anyone else had this issue? and if so what did you do to fix the problem. I should of stated earlier the car has 150,000 miles on it all highway miles its a 70 mile round trip to work everyday. Any help or ideas would be greatly appreciated.