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Q: Car is shaking and smoking out of the tail pipe. I have replaced the spark plugs, alternator, and gaskets. It won't go past 50 mph.

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car is shaking smoking out of tail pipe have replaced spark plugs alternator gaskets wont go past 50 mph will be has major trouble cannot find the problem and its using so much oil

My car has an automatic transmission.

Hi there. Check the following conditions that the engine could consume engine oil.

  • Positive Crankcase Ventilation Valve (PCV) is plugged up forcing engine oil into the combustion chamber
  • Piston oil control rings are worn and leaving excessive engine oil in the combustion chamber
  • Valve guide seals are broken, cracked, or missing causing engine oil to puddle up on the valves making the engine either suck in the oil or spit it into the exhaust system

I recommend start with replacing the PCV Valve and see if the engine stops smoking and begins to run smoother. If the PCV Valve does not cure the situation, then I recommend seeking out a professional, such as one from Your Mechanic, to help you diagnose your engine for oil consumption.

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