VANISHING oil

I have a 2008 Volvo S40. I bought it used less than a year ago, at around 68k miles from a volvo dealership in my area. At just before my 75000 maintenance, I noticed that my oil light flickered while I made turns. Turns out, I was 4-5 quarts low on oil- and took it into my mechanic (a certified volvo mechanic) within two days and without further driving it. Everything goes well- car looks good. Now, at my 82,000 mile maintenance, again, the same flicker of the oil lamp light on my turns- and poof! Oil is down again 5 quarts.
Now, there’s absolutely no sign of leakage or burning, and my mechanic thinks it’s due to carbon build up around the piston rings… this sounds like more of a result of a disguised problem, rather than the cause itself. I don’t use cheap gas, and have done everything according to the service manual. Has anyone else had this problem and can point me in the right direction to resolve this??

Cars burn oil…some more than others. I get how you might be caught multiple quarts low–once–but how could this happen to you twice in a row? The way it reads, you drove a car, with a known oil consumption problem, 7000 miles without once checking the dipstick…is that right?

It takes 3 minutes to read a dipstick at most. A new engine for that car, installed is…$5,000? (just a guess). That works out to an hourly rate of $100,000 to check your oil. So…check your oil each and every fill up until you know what you rate of consumption is. With this new-found info, you should NEVER be more than a quart low again!

P.S. multiple low oil pressure lights means that there is probably already serious engine damage as a result of oil starvation. The oil light is kind of a “the horses have left the barn already” sort of indication.

I second @meanjoe75fan‌ on his observations and advice.

I check my oil often anyway, but especially after the first issue, I would have been paranoid about doing it on a regular basis.

" I don't use cheap gas, and have done everything according to the service manual"

Does this mean you read the service manual? How about the Owners manual?

Page 216 of your owners manual:

The oil level should be checked every time the vehicle is refueled.
• Not checking the oil level regularly can result in serious engine damage if the oil level becomes too low. • Oil that is lower than the specified quality can damage the engine. • Always add oil of the same type and viscosity as already used. • Never fill oil above the MAX mark. This could cause an increase in oil consumption.
"Has anyone else had this problem and can point me in the right direction to resolve this??"

The damage has been done, time to unload this car or get a maintained engine to install. I’m sorry if this sounds harsh, but it’s less harsh than you have treated this engine.

Using your oil pressure light to monitor your oil level (instead of checking the dipstick) has led to you letting your oil run dangerously low. This was likely caused by moderate oil use (burning) by the engine, but when the oil got so low that your oil pressure light came on (twice!), you damaged your engine further, making it burn oil at a faster rate.

Please get into the habit of checking your oil level every time you put gas in the car. Doing this might prevent further damage that could either increase the rate at which this engine burns oil or kill your engine (or both).

Your oil usage is still low enough that they wouldn’t fix it even if it were brand new. All you have to do is add oil and not let it get more than one quart low.

“Has anyone else had this problem and can point me in the right direction to resolve this??”

No, I have not had this problem, but that is because I check my oil often enough so that the dipstick never falls more than 1 qt below the “full” mark. In fact, as soon as the level falls by 1/2 qt, I add oil in order to maintain the level as close to the full mark as is possible.

Pointing you in the right direction essentially consists of advising you to open the hood, pull the dipstick on a regular basis, and add oil as necessary. Normally, doing this every couple of weeks would probably be sufficient, but now that the engine has been repeatedly run low on oil, I would advise that you check (and replenish) the oil on a weekly basis.

You have essentially shot yourself in the foot and all you can do at this point is to carefully monitor the oil usage on an engine that was damaged by your own negligence. Whether you can get 3 more months or 3 more years out of this engine is an unknown, but you can extend its life as much as possible by beginning to be careful about monitoring its oil level.

As to, “there’s absolutely no sign of leakage or burning”, you are not seeing oil smoke because your catalytic converters are “eating” that smoke and thereby concealing the oil burning. The next step, unfortunately, will probably be a need to replace those very costly cat converters. As to the source of the oil burning, that is probably the result of poor maintenance on the part of the previous owner(s), which could include going for extended periods of time between oil changes and/or not checking the oil level between oil changes, and allowing the level to fall too low.

meanjoe75fan has put it perfectly. I hope you have extra money sitting around for a new engine, as you may be needing that sooner or later.

@meanjoefan75 is right on the money. I agree with the other comments as well. I have a brother-in-law who thinks like you do…that maintenance is just used only after the vehicle breaks down. Checking oil is very simple as is checking the other fluids in your vehicle. I even check my wiper fluid level at the same time. My vehicles last a long time because of preventative maintenance. My brother-in-law scraps a lot of his vehicles and I wouldn’t have any of his cars or trucks if he gave them to me.

Everyone should check their oil at least every 1000 miles.
Too bad they don’t put a note on the dash.

Odds are the previous owner(s) did not change the oil often enough and the oil control rings are coked up; meaning frozen due to aged, burnt oil. The fact that you’ve allowed the oil level to get 4 and 5 quarts down and the oil pressure light illuminating means the engine’s days are numbered.

The reason you won’t see smoke is because the converters are catching it. Burnt oil on the converter substrate gradually exits the tailpipe as soot and yes, it can ruin O2 sensors and converters.

No matter what type of car you buy or whether it’s new or used, the hood MUST come up regularly to inspect fluid levels.
You need to plan for the future; either by trading cars or lining up a new engine because that’s where this is headed.

For what it’s worth OP, I’ve torn into more engines than I can possibly remember and coked oil control rings were more prevalent than not.

I often check the oil when I am filling the gas tank. It gives me something to do while I am filling the tank. On many occasions, I have had other motorists come up when I have the hood open and ask my advice on their automotive problems. In this day and age, if you can open the hood, you are considered an automotive expert. I puff out my chest and give the same bad advice that I post on this board–however, it is even more fun giving bad advice face to face.

Okay- in checking the oil, and finding that it was low the first time: with 4,000 miles from the time driven off the lot, and with an oil change before and after… what would the direct cause of the consumed oil have been, since the dealership did not find “anything wrong” with the engine at that first maintenance?

“what would the direct cause of the consumed oil have been”

There’s 68k miles of use that you don’t know the history of regarding oil changes and keeping the oil level up.
That’s plenty of time to abuse the engine and shorten its life.

“the dealership did not find “anything wrong” with the engine at that first maintenance”

The dealership would have to drive it at least a few hundred miles to spot an oil consumption problem.
They’d have to partially disassemble the engine to spot mechanical wear.
Nobody does all that to prepare a used car for sale.

I am in the majority of people that never check their oil, but you sir are in the minority that need to check your oil every so often, as advice above. Sure I only have 155k and get scared after reading comments like these, and go check my oil, but it is always fine. Going out to do it now. Ok Oil is full, a little dirtier than normal, oil change monitor has not gone off, but next couple of weeks an oil change. Thinking the cold winter and poor gas mileage is to blame. There are treatments for coked Piston rings, yamaha whatever is what my boat guy recommended for my boat. Remember all that stuff can clog up the catalytic converter, and add cost to keeping the engine running sweet if you neglect it.

Circuitsmith is correct. Odds are this car was damaged goods when you bought it and running it chronically low on oil just greatly exacerbates the problem.

A brand new car can suffer engine damage inside of 15-20k miles depending upon driving habits, maintenance regimen, and environmental conditions.

With oil consumption this severe you’re really at the point now a decision has to be made about what to do with this car as the current rate of consumption is just generating more problems.

Just curious, but what state do you live in? Some states have laws that may offer a little protection with a used car. If it was sold “AS IS” with a disclaimer that you signed then you may be up the proverbial creek without a paddle. You should have a copy of this if applicable.

hmmm … first time was 5 quarts in 7000 miles, second time the same, 5 quarts in 7000 miles. That is good news in a way as the oil consumption rate is not getting worse. Many newer cars these days – due to the manufacture’s efforts to increase mpg – the owners of almost brand new cars these days see one quart oil loss per 1500 miles. If the owner complains, the dealer will say it is normal. So your Volvo isn’t that much over what is often considered normal oil usage. You might could reduce the rate of loss by switching to a different viscosity I suppose, but me, I’d just use whatever oil the owner’s manual says, check the oil once a week, and top off between changes.

What is causing the loss? It could be the rings as mentioned above. Another common cause is the valve guide seals. Ask someone to watch the tail pipe as you start the car first thing in the morning. If there’s a brief puff of bluish smoke, that’s consistent with the valve guide seals being the cause. Whether you’d even see the puff of smoke upon first start in the morning depends on whether it is trapped by the cat(s) first though. If it was valve guide seals, and you wanted to stop it, those can often be replaced without removing the engine.

I agree with @PvtPublic‌
Dump the car and move on. If you have your oil changed, check your oil IMMEDIATELY. And check for leaks . Then, check it a week later. Then you can stretch out your checks as you can get a feel for oil consumptions. If you can open your hood, you can check your oil. It’s easier then your tires. Manufacturers make it the easiest to do so there is no excuse. My wife, daughter and son all do it when they learned to drive. Everything else is in a tank other then the transmission. That can only leak. So keeping a clean area under the key components helps checj transmission if you find that too difficult. But, have it done at oil change time too. It’s all part of driving a car.

My 2012 4 cylinder Camry’s owners manual say "oil consumption of one quart or less in 500 miles is normal. Sounds like Toyota Knew they had troubles coming down the pike.
Mine doesn’t burn any between changes but I don’t think Toyota would do anything about it if it did.

My 2012 4 cylinder Camry's owners manual say "oil consumption of one quart or less in 500 miles is normal. Sounds like Toyota Knew they had troubles coming down the pike.

ALL manufacturers make that claim.