Hi how are you I noticed a smoke from my exhaust while i am driving down road on the high way when i pull up my feet from the pedal then put it to drive the smoke comes out what its mean i have no overheating the car works properly but my check engine light on from month ago and I replaced the ccv because i have oil burn the oil burn now decrease after this replacement but I still burning some oil
Hey there. Valve stem oil seals (in the cylinder heads) do not last forever and their failure is a possible cause, or contributing cause, to oil getting into the combustion chambers and then burning. Of course, it is also possible that oil is being drawn into the combustion chamber(s) due to worn out piston rings.
If the engine has high mileage (over 150,000 miles), that possibility can be investigated by doing a compression test and subsequent test with oil in the cylinder to see to what extent if any compression rises as the oil "seals" the possibly leaking rings in the cylinder. You should also check to make sure the PCV (positive crankcase ventilation) system is free and clear and operating properly. Failures there can cause oil to be forced into the cylinders when engine vacuum is high (like when you take your foot off the gas). All of these possibilities can be examined by a certified mechanic, like one from YourMechanic, to diagnose the smoke issue.