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Loss/burning of oil?

I have a 2001 Kia Sedona mini van with about 148,000 miles on teh 6 cylinder engine. Since about the first of the year I have noticed a slight loss of engine oil over the past 4 months. It appears to be maybe about a quarter of a quart for about every 1000 miles or so. Up until then I had no issue with loss of oil. It is not leaking out that I can see as there are no drip signs on the underneath or ground, I have had no loss of antifreeze so am not sure how or where the oil might be going. My dad said that as some engines age and with this engine being now almost 11 years old with that many miles it wouldn’t be out of line that the engine is “burning” the oil. Not sure what he means by that, but what might be a reason/s for the slight loss of oil.

Your dad is probably right on, have you notice blue’ish smoke particually at start up?? Its most likley that your valve guide or piston rings are worn to the point that they are letting oil past them. This oil gets burned up in the cylenders with the gas, and sent out the tail pipe. 1/4 Qt every 1000 is not bad at all, so I say dont worry about it… Just keep you eye on the level and keep driving.

Some oil will slip into the cylinder through the valve stem seals and some through the oil control rings on the pistons. At 1 quart per 4000 miles, you don’t have a problem. At any rate, the oil is being burned along with the gasoline. The next time you have an oil change, you might want to try a different brand of oil but with the same viscosity (e.g. 5W-30) and see what happens.

An engine can begin to burn oil when the cylinder walls/oil control rings begin to wear or get stuck. The oil is able to leak past the worn cylinders and worn/stuck rings and gets burned in the combustion chambers.

The rate at which the oil is being consumed is not enough to produce smoke from exhaust. As matter of fact, consumption rate of oil that the engine is using is pretty good for the number of miles on the engine. So I wouldn’t worry about it.

Did you know that some vehicle manufacturers consider the consumption of one quart per 1,000 miles as normal on their new vehicles?

Tester

“It appears to be maybe about a quarter of a quart for about every 1000 miles or so”

That’s not even a quart between changes. I wouldn’t be too concerned about it unless it gets worse.

I’d add that just because there is nothing dripping doesn’t mean you don’t have a leak(s). I have two cars and both leak some oil. On neither one is it enough to leave drips on the ground. They just ooze. I’m sure a drop or two hits the ground here and there, but there are no puddles after I’ve parked them. A lot of it just mixes with dirt and junk, and thickens up and becomes grime on the engine someplace.

First off, congratulations on monitoring your fluids, monitoring your engine, and taking care of your car. I’d expect your car to end its life as one of those with ultra high mileage. Your level of care is what accomplishes it.

1/4 quart on an engine iwth your mileage is excellent, a sign of a good healthy engine. As otheres have said, a little oil useage for an engine with that many miles (and yours is definitely “a little”) is perfectly normal.

Keep up the good work. And never hesitate to stop by if you have any questions.

I’m in agreement with your dad and the others on this forum. As the engine ages parts get worn it’s not uncommon for a car to start to start to burn/leak slight amounts of oil. If this is the case as the car gets older and more miles it will gradually begin using more oil, but if you keep the oil changed regularly and don’t allow the oil level to get too low the engine will likely be good for several more years and miles. By the time my '88 Escort had 300K miles it was using about a quart between 3-4K miles change intervals, it now has 518,600 miles and is up to about 1 quart every 800-1K miles, but is still running. Where most people allow their car to get a full quart low on oil before refilling it to the recommended level I refill when it shows a 1/2 quart low to help prevent wear from happening due to low oil level.

I had a 70’s VW Rabbit one time, and it would burn about one quart in 1000 miles. This was at about 3 years old! The car, not me. I was older. VW at the time said it was normal! They told me it was the valve-stem seals that were wearing, but not to worry, “it was normal”. Then a few months later I saw an article in the newspaper which said there was a recall to replace the valve-stem seals on all VW Rabbits of that vintage. So I took it in, and VW replaced them for free, part of the maintenance. Good for them, I say.

Anyway, I wouldn’t be surprised that if all you are losing is 1/4 quart in 1000 miles, and no visible leaks, you are also experiencing worn valve-stem seals. With the oil so small, I would just check the oil level every 1000 miles and top if off between changes. Don’t worry, be happy!