i went to check a car today. i did compression test the reading was 125 120 125 120.the spark plugs(ngk) look white like they are brand new with a little of tan pigment on them .the spark plug heat range mark is almost at the treads. the sparl plug ring is a little bit black. i put my finger in the muffler there is black staff on it. is the car burning oil or runing rich?
Mar 28, 2015 at 5:43 PM