Oil guzzler OCI conundrum

[PhilloBeddow]

Hey everyone,

My son bought a 2019 Kia Optima (2.4 Theta II GDI) and not surprisingly it just drinks oil. Around a quart per 1000 miles. The recommended OCI from the manual is 7500 miles.

This is a philosophical question almost - if we top up the oil with 7 quarts in between oil changes and the engine has a 5 quart capacity do you really need to drain and fill at 7500 miles? Or just keep changing the filter?

It seems like a bad idea but I can’t exactly say what’s wrong with it.

I’d appreciate any thoughts on the pros and cons and if this has been discussed before please point me towards that thread. I looked but didn’t see anything obvious.

 

[dishdude]

If you're going to try and redeem the settlement from the class action on this engine I would keep up with the OCIs, but if not the engine is clearly on it's way out and I'd do nothing but keep the oil topped off.

 

[dubber09]

I'd not extend OCI beyond 4-5k miles, also, if it burns this much then expect engine to fail.

 

[BigCahuna]

My wife has a '11 Chevy Equinox that has a rep for eating oil. When we first got it, it would use 1 qt every 750 miles. No leaks that we could find. Even the dealer wasn't going to do anything unless we wanted to pay them to rebuild the engine. My solution was to run a heavier grade oil then what gm said to run. I found that by running 10w40 wt. instead of 5w30 wt, I can go almost 2000 miles without having to add oil. I find that way cheaper than rebuilding the engine. By the way, this car has 93k miles on it and we know the original owner had all service work done at the dealer, before we bought it with 35 k on it. Unless you have a bad leak, I would try the heavy oil route. We haven't seen any performance issues in 7 years of ownership using that wt oil.,,

 

[burbguy82]

Hey everyone,

My son bought a 2019 Kia Optima (2.4 Theta II GDI) and not surprisingly it just drinks oil. Around a quart per 1000 miles. The recommended OCI from the manual is 7500 miles.

This is a philosophical question almost - if we top up the oil with 7 quarts in between oil changes and the engine has a 5 quart capacity do you really need to drain and fill at 7500 miles? Or just keep changing the filter?

It seems like a bad idea but I can’t exactly say what’s wrong with it.

I’d appreciate any thoughts on the pros and cons and if this has been discussed before please point me towards that thread. I looked but didn’t see anything obvious.

In my lightly educated opinion, with that amount of consumption, I would just change the filter every 5k.

You are replenishing 20% of the oil every 1000 miles, so what is the advantage of draining the sump? To get nasties off the bottom? Maybe.

 

[BrendanC]

the 05 accord in my sig burns about a quart/1k miles. i’m just topping off and will do an actual oil change at 12k miles. run a good filter and don’t worry about it for 10-12k miles IMO.

 

[MrBaumTastic]

I've wondered about this too. My 2019 Kia Sportage consumes the same amount but I stick with 5k OCIs out of habit and because I like doing it.

 

[Marcozi]

Why do these engines burn oil? Oil control rings?

 

[Donald]

What does the Kia dealer say about this? I would think it's above what Kia should say is normal.

You could try a piston soak.

Is the compression with normal specs?

Visible is exhaust?

 

[SC Maintenance]

Why do these engines burn oil? Oil control rings?

Ask 5 experts - get 6 answers. Poor rings, bad machining, bad valve guides all have been floated. There was a class action where no one admitted anything. The Theta 2 engine was the worst, but the NU engine burned also, at least for some years.

They say its fixed now

Best just to avoid them used altogether, IMHO - which is unfortunate because the rest of the cars seem decent for the price.

 

[svtrit]

We put a new filter on my son’s Camry that leaks oil at about a quart every 500 miles once a year. When he graduates from UN that car is going away.

Adding oil was less expensive than the repair.

 

[PhilloBeddow]

Thanks for all the responses. I was trying to wrap my head around the idea of just topping up the oil rather than drain and fill so I didn't include any of the vehicle details.

Since almost all the responses are about the very practical details of not blowing up the engine or preserving the warranty here's the vehicles story -

• Purchased used at 86,000 miles from a non-Kia dealer. Serviced by the dealer before sale
• First oil change free at the same dealer (that was at 91,000 miles)
• Oil & filter changed at 95000 and 101000 miles with Valvoline restore and protect 5w30 (owners manual calls for 5w20)
• PCV valve changed at 95000 miles
• Mileage is now over 100,000 miles so factory warranty no longer applies. The dealer did an upsell for a 30,000 mile / 3 year extended warranty that my son purchased. I advised against this but it's his first car purchase after college so not my car loan. If I knew then what I know now about the Theta II engine I would have changed my tune.
• Checking the VIN against the covered vehicles at the class action lawsuit website, this particular vehicle isn't covered.

He's on vacation at Disneyworld right now so almost 2000 miles of freeway driving to let the VRP work its mojo and a tank of gas with Berrymans B12 as the latest maintenance step. A piston soak has been suggested but I'll wait and see how the oil consumption looks after he gets back from Disney.

Any other suggestions not covered by the above?

p.s. Merry Christmas everyone!

 

[dishdude]

Thanks for all the responses. I was trying to wrap my head around the idea of just topping up the oil rather than drain and fill so I didn't include any of the vehicle details.

Since almost all the responses are about the very practical details of not blowing up the engine or preserving the warranty here's the vehicles story -

• Purchased used at 86,000 miles from a non-Kia dealer. Serviced by the dealer before sale
• First oil change free at the same dealer (that was at 91,000 miles)
• Oil & filter changed at 95000 and 101000 miles with Valvoline restore and protect 5w30 (owners manual calls for 5w20)
• PCV valve changed at 95000 miles
• Mileage is now over 100,000 miles so factory warranty no longer applies. The dealer did an upsell for a 30,000 mile / 3 year extended warranty that my son purchased. I advised against this but it's his first car purchase after college so not my car loan. If I knew then what I know now about the Theta II engine I would have changed my tune.
• Checking the VIN against the covered vehicles at the class action lawsuit website, this particular vehicle isn't covered.

He's on vacation at Disneyworld right now so almost 2000 miles of freeway driving to let the VRP work its mojo and a tank of gas with Berrymans B12 as the latest maintenance step. A piston soak has been suggested but I'll wait and see how the oil consumption looks after he gets back from Disney.

Any other suggestions not covered by the above?

p.s. Merry Christmas everyone!

The 100,000 mi factory warranty is only for the original buyer.

If he has an extended warranty, he needs to keep up on and document regular ocis.

 

[TumblrDucks]

Thanks for all the responses. I was trying to wrap my head around the idea of just topping up the oil rather than drain and fill so I didn't include any of the vehicle details.

Since almost all the responses are about the very practical details of not blowing up the engine or preserving the warranty here's the vehicles story -

• Purchased used at 86,000 miles from a non-Kia dealer. Serviced by the dealer before sale
• First oil change free at the same dealer (that was at 91,000 miles)
• Oil & filter changed at 95000 and 101000 miles with Valvoline restore and protect 5w30 (owners manual calls for 5w20)
• PCV valve changed at 95000 miles
• Mileage is now over 100,000 miles so factory warranty no longer applies. The dealer did an upsell for a 30,000 mile / 3 year extended warranty that my son purchased. I advised against this but it's his first car purchase after college so not my car loan. If I knew then what I know now about the Theta II engine I would have changed my tune.
• Checking the VIN against the covered vehicles at the class action lawsuit website, this particular vehicle isn't covered.

He's on vacation at Disneyworld right now so almost 2000 miles of freeway driving to let the VRP work its mojo and a tank of gas with Berrymans B12 as the latest maintenance step. A piston soak has been suggested but I'll wait and see how the oil consumption looks after he gets back from Disney.

Any other suggestions not covered by the above?

p.s. Merry Christmas everyone!

Keep doing VRP with top off for 4-5 OCI to see if anything improves. If not, I don't think Theta2 worth a tear down and piston soak. Just keep feeding cheap 5w30 to it and check oil level frequently.

Merry Christmas Phillo!

 

[PhilloBeddow]

The 100,000 mi factory warranty is only for the original buyer.

If he has an extended warranty, he needs to keep up on and document regular ocis.

Understood and agreed. At least until the extended warranty expires.

Even then I expect I’ll be beating the drum about regular preventative maintenance just to drum good habits into my son. He’s got to learn sometime…

 

[johnmyster]

Instead of discarding, you could use the oil that comes out of it for top-off.

 

[Cruisin'n5thgear]

Assuming linear degredation of oil, the average mileage of the oil in the sump is defined by this equation, solved for your situation, you could replace the oil indefinitely at 1 quart per 1,000 miles and the highest average miles on the oil in the sump would get to 5,000 miles and no more.

Not that I'm suggesting to never change the oil - linear degredation isn't completely realistic. But this illustrates how effective such an aggressive oil consumption is at keeping the average fill in the sump quite young, mileage-wise.

 

[Dave9]

The thing about owning a ticking time bomb is that when you see the timer getting closer to zero, it's time to cut the red wire (sell it).

If you'd rather replace the cats and O2 sensors and then the whole engine, you must really like that car! I can appreciate extra burden for something you like, and a quart of oil isn't exactly expensive, but I'd get real tired of putting a quart in every 1K mi. for something that is more like an everyday commuter than an adult toy class vehicle.

 

[PhilloBeddow]

Assuming linear degredation of oil, the average mileage of the oil in the sump is defined by this equation, solved for your situation, you could replace the oil indefinitely at 1 quart per 1,000 miles and the highest average miles on the oil in the sump would get to 5,000 miles and no more.

Not that I'm suggesting to never change the oil - linear degredation isn't completely realistic. But this illustrates how effective such an aggressive oil consumption is at keeping the average fill in the sump quite young, mileage-wise.View attachment 255200

Thanks for the formula. I was thinking along those lines and that’s what led to my original post.

Fortunately 1 quart in a 5 quart capacity makes for easy math - that’s 20% each top up or 80% of the original fill left. At the second top up there’s 80% of 80% of the original fill (and so on) or 5 x (0.8^n) quarts of the original 5 quarts left where n is the number of top ups.

I didn’t think it through in this much detail originally but it seemed like the quantity of original oil will approach zero asymptotically and so I agree with your point that sooner or later I’ll have to drain the oil.

And they tried to tell me I’d never need high school math! I just had to wait until I’m retired

 

[michaelluscher]

Check the production date on the door placard
May 21, 2018 to February 28, 2019
Does his fall into that range?

Kia's web VIN check isn't as thorough as Hyundai's, you might be better served by dropping into your local Kia service department and having someone run the VIN on the spot for PI1805

https://static.nhtsa.gov/odi/tsbs/2020/MC-10173259-0001.pdf

I'd start thinking about piston soaks/idle flushes and 5w40 oil
It's made some leeway on a '17 Optima and '11 Sonata I look after
The Optima was burning 1qt every ~200 miles, and fouling out a spark plug every ~10 days
1 piston soak and idle flush + Delo 5w40 took that up to ~1,000 miles per qt
Hopefully rinsing and repeating will improve the situation