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Q: Significant cloud of blue smoke from exhaust noticed when I had been coasting for a short time then hit the gas.

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My wife has followed me in her car and mentioned that occasionally there was blue smoke coming from my exhaust. She said it was not a constant flow of blue smoke. I have notice in the rear view mirror it seems to be significant when I coast for a while then give it a significant amount of gas. I am putting a quart of oil in probably every couple months or so and I drive about 1,000 miles per month. I wanted to drive the car one more year then trade it at the end of 2017 but I don't want to get into a significant costly repair before I do.

My car has 111000 miles.
My car has an automatic transmission.

A: What you have described is normal oil consu...

What you have described is normal oil consumption for a vehicle pushing 200,000 miles. It may be a little premature at 111,000 miles. Even so, this condition is fairly normal and manageable. I personally own a Toyota Avalon that used the same amount of oil. The rule of thumb for oil consumption is when you are using more oil between oil changes than is manageable, then it is time to replace the rings or valve stem seals. In your case, I suspect the valve stem seals are the main culprit because air is sucked into the PCV system during off throttle conditions when slowing. The PCV system is part of the valve cover system and the valve stem seals are housed under the valve covers. When valve stem seals become brittle, they can no longer seal as they should and will allow the negative pressure in the crankcase to suck oil into the cylinders and burning the oil. This is what you are seeing in the form of blue smoke out the tail pipe under off throttle deceleration.

Most likely the oil consumption is a product of oil entering the cylinder via the piston rings and the valve stem seals. I am leaning toward the valve stem seals as being your primary failure. This is good news because this is a much easier repair that takes significantly less time. Even so, it is not something you need to do immediately unless the oil consumption becomes worse.

I would suggest checking your PCV valve. If it has never been replaced, they are fairly cheap so I would suggest replacing it. Take some time to inspect any plastic hoses that are part of the PCV system as well. Also, check inside the air box or air hose where the PCV hoses link to. If there is a significant amount of oil in there, clean it and monitor it periodically. This is often an easy way to monitor the PCV oil consumption.

If you decide something needs to be done, I first recommend a more thorough diagnosis by an experienced technician. I recommend the following inspection if you decide you should need further help. Oil level is low inspection Send the technician a note letting him or her know your exact symptoms so he or she can come better prepared.

Good luck!

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