* Coolant Leak: This is the most probable cause. Even a small coolant leak can produce white smoke, especially if it's contacting hot engine parts. The smoke will appear more like steam, and the sweet smell of coolant might be noticeable. Check your coolant reservoir level. Look carefully under the hood for any visible leaks, paying attention to hoses, the radiator, the water pump, and the engine block itself.
* Crankcase Ventilation System (PCV) Issue: A malfunctioning PCV valve or a clogged crankcase ventilation system can allow oil and moisture to escape into the exhaust system, producing white or bluish-white smoke. This is often accompanied by a burning oil smell.
* Head Gasket Leak (less likely with normal temp): While a head gasket leak *can* cause white smoke, it's more likely to cause overheating. If the leak is minor and only allowing a small amount of coolant into the combustion chamber, you might not see a temperature increase, but the white smoke would still be present. This is less likely given the normal temperature reading.
* Condensation (least likely): On cold, damp mornings, you might see some white exhaust smoke, which is simply condensation. This usually clears up quickly as the engine warms up. If this is happening consistently, even on warm days, it's less likely the cause.
What to do:
1. Check the coolant level: This is the most important first step. Low coolant strongly suggests a leak.
2. Inspect for leaks: Carefully examine all coolant hoses, the radiator, the water pump, and the engine block for any signs of leaks.
3. Check the oil: Look for milky or frothy oil (indicative of coolant mixing with oil), which points to a head gasket or crack in the engine block.
4. Smell the smoke: A sweet smell often indicates coolant, while a burning oil smell suggests a problem with the PCV system or oil leak.
5. If you're not comfortable inspecting the engine yourself, take it to a mechanic. Diagnosing this issue accurately requires a proper inspection.
Ignoring a white smoke issue can lead to serious engine damage, so prompt attention is crucial.
