Oil leaking from somewhere

Tiny
TOTALMC
  • MEMBER
  • 2012 HYUNDAI SONATA
  • 2.4L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 125,000 MILES
As soon as the car is started, oil gushes from somewhere in the middle of the motor

I thought it was a broken line coming out of the oil cooler, but upon further inspection, those lines
lead to the thermostat and are for coolant to circulate around the oil cooler

Then I found that the throttle body was full of oil (and I imagine the intake as well). So, I'm thinking this must have something to do with my issue

Any ideas on what could be causing this?

Thanks in advance.
Saturday, May 28th, 2022 AT 5:21 PM

21 Replies

Tiny
JACOBANDNICKOLAS
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Hi,

Are you certain it is engine oil? If so, could you upload a pic of approximately where you see it coming from?

The first thing that I thought of was whether the oil filter is leaking or the oil pressure switch. Check both. I attached a pic below showing the location of the oil pressure switch.

Let me know.

Joe

See pic below.
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Saturday, May 28th, 2022 AT 10:56 PM
Tiny
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It's definitely oil, and I couldn't find an external source of the leak. Seems to be middle of the engine, behind throttle body towards firewall

Leaking about as fast as you can pour it out of the bottle

When I removed the air intake / filter housing (everything in front of the throttle body) to get a better look, I noticed some oil at the bottom of the butterfly - and when I pushed it in it was full, close to a pint spilled out when I remove the throttle body

The filter housing is fine - when under the car, the leak is coming somewhere from the driver's side about a foot above the oil filter housing (driver side of intake manifold). The oil pressure switch from the pic you sent looks to be passenger side and take manifold and that still wouldn't explain a throttle body and intake full of oil, right?

Thanks again in advance.
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Sunday, May 29th, 2022 AT 8:23 AM
Tiny
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If it is leaking that badly and is getting into the throttle body (which should be sealed), remove the PCV valve and see if it is full of oil. (See pics 1 and 2). Also, just to confirm, this isn't a 2.0L turbo, correct?

I ask because if it is getting into the TB, it has to be going through the airbox. That is confusing me. Check the PCV.

Let me know.

Joe

See pics below.
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Sunday, May 29th, 2022 AT 7:56 PM
Tiny
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It's the 2.4.

I disconnected the hose labeled "3" when I removed the air box, there was no oil evident.

The front of the throttle body looked clean, seems like it's coming from behind it somewhere in the intake.

Is that hose labeled "1" where the PCV flows into the intake?
(I think "B" in the pic is the PCV valve, correct?).

Could too much oil in the crankcase end up flowing through there into the intake?

I can't think of any other way for oil to even get in there.
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Sunday, May 29th, 2022 AT 9:00 PM
Tiny
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If it is flowing through the PCV, where would it actually be coming out of the intake to make it to the ground?

I'll check the PCV next time I'm there. I'm also thinking of draining the oil to see how much is actually in it, and if it's actually all oil (I had a thought that if a head gasket blew it could have filled the crank case with coolant, resulting in too much fluid in the crankcase, pushing through the PCV into the intake)

Thanks again for any and all ideas.
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Sunday, May 29th, 2022 AT 9:08 PM
Tiny
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Hi,

Check the oil level. That is a good idea. And yes, letter B shows the PCV valve. Also, the other is where it connects. But, if it is flowing from the engine into the TB,

Could you take a few pics of where you feel the leak is coming from?

Also, make sure the PCV isn't clogged. If it's good, then I may suggest a compression test. Something may be creating too much crankcase pressure.

Let me know.

Joe
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Sunday, May 29th, 2022 AT 9:44 PM
Tiny
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When I was underneath it with it running, oil seemed to be gushing from somewhere behind the throttle body and down on my face, limiting my view.

I'll try to get some more info next time I'm there.

If this helps, I found a broken engine mount (top on passenger side) maybe excess engine movement caused the issue somehow.
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Sunday, May 29th, 2022 AT 10:07 PM
Tiny
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Hi,

I'm trying to picture what could cause that bad of a leak from that area, and I'm at a loss. As far as the mount, certainly, excessive movement in the engine can cause issues and damage.

Let me know.

Joe
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Sunday, May 29th, 2022 AT 10:17 PM
Tiny
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If I do find the PCV full of oil, what could be possible causes, besides too much oil in the crankcase?
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Monday, May 30th, 2022 AT 8:16 PM
Tiny
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It could indicate excessive blowby in the engine which is usually the result of worn piston rings.

Joe
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Monday, May 30th, 2022 AT 9:27 PM
Tiny
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Okay, so here's the latest:

There's no oil visible in the tube from the PCV to the intake, and the crankcase has the proper amount of 100% oil.

What other source could be filling the intake with oil?

Thanks again.
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Friday, June 3rd, 2022 AT 11:34 AM
Tiny
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That is a great question. There are three primary things that can cause this to happen. It could be a plugged PCV (which you checked), if the engine oil hasn't been maintained causing internal dirt build-up and excessive pressure forcing it through the PCV, or the compression rings are worn and allowing excessive crankcase pressure to force oil vapors or oil to be forced through the (again PCV/Breather) into the air box.

Just to confirm. The PCV is good, there is no evidence of oil in the PCV hose/breather hose, and there is oil in the air intake to the throttle body, correct?

Also, the oil that was leaking badly from the center of the engine hasn't been located, correct? Are you certain that it was oil? I ask because you said the oil is full.

I know there was a recall related to engine oil consumption. If you look below, I copied one of the issues related to the recall. It was piston compression rings. See pic 1. The interesting thing is this. The only thing that can allow oil to get to the air induction tube and the throttle body has to come through the PCV/Breather. There really isn't any other way. If you had or still have a major leak, is it possible that somehow the leaking oil made its way to the air box and was drawn in?

Let me know. Also, because there is a recall on the engine, contact a Hyundai dealership and describe what is happening to see if it is related to the recall. I know they were replacing engines. (I don't work for Hyundai) I'm suggesting this because I know there was an issue.

Let me know. Also, let me know if you ever determine where the major leak originated.

Take care,

Joe
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Friday, June 3rd, 2022 AT 8:20 PM
Tiny
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Okay, so I finally found the leak

While trying to remove the intake manifold, I found some big chunks of aluminum underneath. After feeling around, I found a hole so big in the side of the engine case I could stick all four fingers in it.

Funny thing is the engine still ran and didn't sound that bad, even though I imagine it must have been a connecting rod that came through the case.
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Saturday, June 25th, 2022 AT 12:59 PM
Tiny
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Hi,

Wow! That isn't something I expected. Did you hear a knocking or anything prior to the leak starting? And yes, it does sound like a connecting rod.

By any chance, could you take a couple of pictures of the damage and upload it? I have a feeling it will help others in the future.

Let me know. Also, I would like to say I'm happy you found the leak, but this doesn't feel like a happy moment. More frustration. But we may have a leg to stand on. It will take some arguing with the manufacturer, but I would try.

I attached a recall below where Hyundai extended the engine warranty to 10 years 120K due to connecting rod bearing wear. This sounds like where the problem came from. The only issue is you are at 125K and close to the 10 years if that hasn't already expired. That is where the arguing will come in. They should replace the engine with a new one free of charge.

Let me know if you want to pursue this. I attached the recall below. Take a look at it and let me know if you have questions.

Take care,

Joe,

See pic below.
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Saturday, June 25th, 2022 AT 9:04 PM
Tiny
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Okay, I informed the customer there may be a recall - and he did call Hyundai, they said there are known problems with this generation motor, and it may be covered.

I was unable to get a picture of the hole. So much oil under the manifold, between that and the 105° heat - it was difficult holding the wrench to remove those bottom bolts

It seemed the hole was a few inches below the knock sensor - on a portion of the engine case more facing up, rather than the flat side facing front.
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Saturday, June 25th, 2022 AT 9:34 PM
Tiny
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Thanks again for all your input.
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Saturday, June 25th, 2022 AT 9:35 PM
Tiny
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Hi,

The idea that you heard a knock originally leads me to think this is the cause. The TSB I attached above is from Hyundai, so I have no idea why they are saying it doesn't exist.

Tell your customer the TSB number. See pic below of the original TSB.

Interestingly, shortly after I responded to you, I answered a locked-up engine on a 2015. He has the same engine. It seems like this is going to become a very popular concern/problem. LOL

Let me know.

Joe

See pic below.
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Saturday, June 25th, 2022 AT 11:20 PM
Tiny
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I believe that it was another customer of mine's 2015. I had questions open on both of them at the same time.

Needless to say, I recommend unless the replacement is free. Maybe better off with a different car.
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Sunday, June 26th, 2022 AT 8:54 AM
Tiny
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Hi,

That may be the best advice you can give. I'm not familiar with the condition of the vehicles. However, I would certainly cause an uproar with Hyundai and try to get the engine replaced. How was the owner to know there was a problem if they were never notified?

Let me know. And take care of yourself.

Joe
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Sunday, June 26th, 2022 AT 8:56 PM
Tiny
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They both looked like new. I cannot attest to the driving conditions when the problems happened - but both customers stated it just happened suddenly, without warning.
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Sunday, June 26th, 2022 AT 9:08 PM

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