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Q: Burning engine oil and have gray smoke coming from below the engine and the tailpipe.

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I bought a car with little oil in it 3rd party. I got an oil change and started to drive home 4 hours away and the oil light came on. I stopped and checked the oil and all was burned after I drove it 200 miles and I added 3 more quarts and it was burned off after 150 miles. There is gray smoke coming from below the engine and the tailpipe. There is no dripping oil on the ground. I took it in to a shop and they said oil was in the combustion chamber(spark plug well I believe). They said I had to rebuild the engine or get a new engine. Is this the only course of action? Is there anything else I can do?

Hi there. If you are getting gray smoke from under the vehicle and in the engine compartment, then there is an external oil leak. The oil is leaking onto the exhaust pipe and then burning off. This is why you are not seeing any oil on the ground. As for the engine smoking some oil, then the valve guide seals on the cylinder heads are possibly leaking causing oil to enter the combustion chamber through the intake valves.. Another way that the engine could be getting oil into the combustion is having a positive crankcase ventilation valve (PCV valve) being stuck causing oil to enter the intake system. To check this, check the intake tubing and see if there is any oil present. If there is oil present, then I recommend replacing the PCV valve to prevent any oil from going into the combustion chamber. The external oil leaks could be, a leaking front engine seal, a leaking rear main seal, a loose oil filter, oil cooler lines could be split or loose, or a valve cover gasket could be leaking. If you need further assistance with your engine using a lot of engine oil, then seek out a professional, such as one from Your Mechanic, to help you.

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