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Knocking noise engine area

I have a 2012 Kia Optima hybrid. Last Saturday night I was driving home on the interstate and out of no where my car started making a faint noise. It slowly progressed to a loud knocking noise and had trouble accelerating. I was on the highway so I had to accelerate to go the speed limit. The more I accelerated the louder the noise got and it seemed as though the car was having a hard time maintaining speed. This happened for about 15-20 miles.

I eventually got home safely and the knocking noise was pretty loud. I turned off my car and the next morning checked the oil. Previously the oil light would flash sometimes when accelerating but I didn’t think much of it. So, when I check the oil, there was no oil at all. Not even a drop. It looked completely dry. I went to the store, bought oil and added all 5 quarts. My boyfriend picked me up because I already had plans to travel to my parents house, which is three hours away, for Christmas and did not want to drive my car after experiencing that.

I got an oil change at a local mechanic on September 14 this year. The next service date on my windshield sticker says December 13 at 143,000 miles. My car is currently at 143,616 miles. Today I called the mechanic that did my oil change and they said they are going to send one of their guys over to check out my car tomorrow. I decided to turn on the car and move it around the parking lot to see how it was doing since adding the oil but then noticed the engine light came on. As of now, I feel unprepared for when they come check my car tomorrow because I don’t know what the problem might be or what to say. What do I do? What do you think is the problem? Are they at fault?

It might be possible they are at fault, an oil loss due to drain plug or filter issues, the ultimate responsibility for checking the oil level is a customer responsibility. One can only hope the engine survived the incident and you can carry on. If you can check that the oil drain plug or filter are there and not leaking with pics might be helpful if future litigation is needed.

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Very much dought it is there fault have you checked the oil level since sept.seem’s to me if it was drain plug or filter it would have showed up a lot sooner.

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4 months… plenty of time for your engine to use up enough oil to kill your engine. The flickering red light should have been a warning to you to check your oil. So why wait 4 months? You will be VERY lucky not to have destroyed the engine.

Sorry but this is your fault, not the mechanic that did the oil change. Any mistake he made would have shown up 3 months ago.

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Nothing showing on the dipstick does NOT mean there is no oil left in the crankcase. The sign for that is the engine seizing in very short order. You have likely overfilled the oil by 2 or 3 quarts. This is almost as bad as the oil being low by the same amount. Check the dipstick now. I will bet that the level is way over the full mark.

I’m not optimistic that the engine hasn’t suffered significant damage.

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The knocking is a hint tho…

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Knocking could be a hint that the engine isn’t getting enough oil. Whether there’s any in the crankcase is unknown. It could also be caused by overheating. If there’s no oil showing on the dipstick the OP is probably down 3 quarts or more, which doesn’t leave much. The OP’s vehicle has a capacity of 4.8 quarts, call it 5 in round numbers. And if the shop that did her oil change recommended another after 3k that means her vehicle consumed/leaked about a quart every 1k, maybe more. We’ll probably never know since she apparently doesn’t check it even when the oil light flickers. She may get away with fairly minor engine damage but I’m not hopeful.

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No

After you posted the following, I think it is obvious…

I realize that this likely won’t help with your current car, but with all of your future vehicles, try to remember that checking the oil once per week is a good idea. In fact, many manufacturers state that you should check the dipstick every time that you fill your gas tank. Take a look at your Owner’s Manual, and you will likely see some verbiage to that effect.

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Has your mechanic ever alerted you to low oil levels when they changed your oil before? If I drained out 2 qts I might tell customer. Good question for mechanics here. Anyone ever run into this situation and then talk to car owner?

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I doubt if hardly any of the oil change people even pay attention to the oil draining out . It just goes into a large container and while it is draining they are replacing the filter and checking the things they are told to check. Such as tire pressure and thread depth .

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Some shops do check the oil first, or at least pretend they did. A few years ago the nice folks at Jiffy Lube told me there was no oil showing on my Corolla’s dip stick, which I knew was a lie. One of the reasons I no longer go to Jiffy Lube. To this day the car uses about 1/2 quart in 4k.

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Sorry you are having this difficulty. Keep your fingers crossed, you may get lucky, but I expect you’re in for some bad news. The engine oil warning light should never turn on while your are driving the car. If it does, even if it just flickers during brief accelerations, it means something may be seriously wrong and must be checked immediately. If it is flickering and you hear a knocking sound, or it ever turns on steady, the engine should be turned off immediately.

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We used to service a fleet of delivery trucks. When One of the trucks would come in for the oil change, it was always low. The last time I did this truck, my boss told me to put the drained oil in a jug. He took the 2 quarts of oil I drained out and bring it to the companies manager. It was supposed to hold around 8 quarts.

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When I was working at the dealership, I ran into that scenario quite a few times

I learned something . . . when dealing with very expensive vehicles, the owner does NOT want to hear that their engine is consuming oil. It seems I spent more time explaining the multiple reasons why an engine can consume oil, versus the actual oil and filter change. And it just made them upset, many of them were hearing me say their expensive vehicle were less than perfect, which was something they could not emotionally bring themselves to accept. Not a single one of them was grateful for the information. Many of them even wanted to shoot the messenger. Translation . . . it was opening a can of worms, and absolutely NOT worth it for me

On the other hand . . . now that I’ve been working for a fleet the last few years, many of the vehicle operators ARE grateful for this kind of information. Some of them come by every week or so, to have their engine oil level checked and topped off, as needed. It’s kept many an engine going, which consumed copious quantities of oil

In our fleet, the vehicle operators are not allowed to stock up on fluids for their work vehicles. I believe the fear is that some of them would instead take it for their personal vehicles. So if they’re low on fluids, they need to stop by the shop. They usually do this first thing in the morning, before headed out to their assigned work location.

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Wonder how much a shop charges to check your oil, and add if needed.

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Do you park in the same place regularly, if you do have you checked or look on the ground to see if there is an oil spot. If the mechanic left the drain plug or filter not properly attached and it was leaking there would be a oil spot on the ground.

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I’d say it’s a perfect alignment of factors that puts ZERO blame on the garage. You have a vehicle with over 140,000miles on it that developed a fault for which you ignored 2 clear signals 1: a flickering dash warning light 2: An audible knock which you chose to accelerate through and make louder rather than stop. The clincher is that you’re 600miles beyond when they recommended the next oil service!
It’s unclear which came first, the knock or the oil loss, but it is likely low oil caused it.
Neither are especially surprising for a Korean vehicle with 143,000 miles - either burning oil OR exhibiting bottom end bearing wear or cam/valvetrain issues. I wouldn’t be surprised if it’s a bearing failure ir bent valve but these engines may have hydraulic lifters which rely on engine oil which could also result in noise plus loss of power. That might be the best case scenario here - loss of oil pressure causing valve-train slop.

But to answer the original question: You do know what to say to them, describe exactly what happened. You’re not expected to diagnose the fault and trying to do so can actually interfere with a proper diagnosis. Good luck.

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