Hello John T.,
A cloud of blue smoke is typically indicative of oil being burned in the combustion chamber. Here's a comprehensive look into the potential causes and solutions:
1. Worn Piston Rings:
Pros: Replacing piston rings can restore compression and reduce oil consumption. Cons: This is an intensive repair and can be costly. Requires engine disassembly.
2. Faulty Valve Seals or Valve Guides:
Pros: Addressing the valve seals or guides can prevent oil from leaking into the combustion chamber. Cons: This also requires significant work and can be somewhat costly, but it's usually less intensive than piston rings.
3. PCV System Malfunction:
Pros: Replacing a faulty PCV valve is relatively easy and inexpensive. Cons: If the PCV system isn't the issue, this won't resolve the blue smoke.
4. Turbocharger Wear (if equipped):
Pros: Addressing issues with a worn turbocharger can resolve oil leaks into the combustion process. Cons: Turbochargers can be costly to replace or repair.
5. Overfilled Engine Oil:
Pros: This is an easy fix; simply drain the excess oil to reach the correct level. Cons: If you've been maintaining the vehicle well and haven't added oil recently, this is less likely to be the issue.
Evaluation:
Given the sudden appearance of blue smoke after a hard acceleration and no prior issues, I'd suspect it might be related to the Positive Crankcase Ventilation (PCV) system (option 3). During hard acceleration, any malfunction in this system might cause oil to be drawn into the combustion chamber, leading to burning and the subsequent smoke. This is a relatively common issue and could explain why your sister-in-law experienced something similar in her Elantra.
Suggestion for Moving Forward:
- Check the engine oil level to ensure it's not overfilled. If it is, drain the excess oil.
- Inspect the PCV valve and system. A stuck or malfunctioning PCV valve can allow oil to be sucked into the intake and then burned in the combustion chamber.
- If the issue persists, consider a professional diagnosis. They can conduct a compression test or a leak-down test to ascertain the health of the piston rings and valves.
- As a last resort, if the problem persists and the vehicle has a turbocharger, inspect it for wear or oil leaks.
- If none of the above addresses the problem, a deeper inspection of the engine internals might be required. Given the age and mileage of the car, I'd start with the simpler, more common issues like the PCV system before moving on to more complex diagnoses. It's always advisable to consult with a trusted mechanic to ensure the right diagnosis and solution. Good luck, John T!