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Q: Bluish exhaust smoke upon startup

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My car has gone 130,000 miles. The car runs well. However, it makes white to bluish-colored smoke each time I start it. It comes from the exhaust in huge amounts. I had the oil checked and it is at an appropriate level. What might cause the smoke?

With higher mileage like your vehicle has, the exhaust valve stem seals wear, allowing a tiny amount of oil to seep onto the exhaust valve while the car is sitting. When you start it up, this oil is burned up (clogging the catalytic converter as well), and causing the blue smoke you see briefly. If you would like to have this looked at, a certified technician from YourMechanic can come to your car’s location to diagnose the smoke problem and figure out what fixes are appropriate.

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