Car using oil, but no smoke in the exhaust
Symptom: The car uses more oil than normal, but there is no trace of smoke from the exhaust. The oil level is low between oil changes. You never noticed it before and it doesn’t appear that the oil is being burned by the engine. There is not a trace of smoke in the exhaust.
1. The PCV system is not working properly.
The Fix: Replace PCV valve.
2. The engine may have mechanical problems.
The Fix: Check compression to determine engine condition.
3. The engine’s valve seals may be worn.
The Fix: Replace valve seals. (Generally not a DIY job)
4. The engine’s gaskets and seals may be damaged.
The Fix: Replace gaskets and seals as required.