Awaiting new Hyundai Theta II Engine Install

[snail415]

Hi all,

First post here on the forum. I have a 9 year-old Hyundai Sonata (2017) that I purchased new. It only has 50k miles at time of this post. While I changed oil every 5k miles, I never had to research all of the gremlins this engine is known-for. It’s been a solid car for most of our time with it, and it saw nothing but short trips and not even work commutes. Given the low mileage, I’m assuming we just got lucky for nearly a decade and were due for the inevitable. Thank goodness it’s still under warranty.

For the first time ever last week, the car went into limp-mode. I confirmed it threw the 1386 code (crank sensor). Car is now at the dealer, and so-far the service department is signaling that a new motor is likely.

If it pans-out that way, I’d appreciate recommended break-in oil types/viscocity/schedules specific to this type of engine (modern, poorly-assembled GDI) and circumstance (might only getting a new long-block). If you’re experienced with this engine and any successful mitigation strategy, I’d appreciate your take. We need this car to last as long as possible.

As an aside, I’m a fan of Super Tech synthetic oils and wonder if anyone could weigh-in on the utility of using their conventional variant before migrating to FS (for break-in). If I’m simplifying the matter, or if this has been covered at-length, please forgive my ignorance. I’d like input and perspective as current as possible. Thanks in advance.

 

[CarLuver]

my kids 2019 w 2.4 tucson starting burning oil at 90k . like you i was religious in changing oil every 5k and using a oem hyundai filter . since it was under warranty , the dealer replaced the engine . so far only 3k on the engine . it has though burned 1/2 quart of oil . since its got over 100k on it now the next step is to buy a new vehicle if it gets worse .

 

[Propflux01]

No need for a conventional oil break-in. Just use your normal Stupertech 5w-30 oil and change it no later than 5000 miles.

 

[WarEagle]

For off the shelf I’d highly recommend Mobil 1 ESP 0w-30 or Valvoline Restore and Protect 5w-30 with OCI 4-5k miles. Would also recommend a premium guard filter such as Carquest premium/EP or microgard select.

My daughter has a 2019 Santa Fe with 90k miles and will be using Mobil 1 Advanced Clean 5w-30 (got it on sale) next OCI before switching to HPL premium plus 5w-30 for as long as we own it

 

[tired]

like you i was religious in changing oil every 5k and using a oem hyundai filter

Which oil did you use?

If it pans-out that way, I’d appreciate recommended break-in oil types/viscocity/schedules specific to this type of engine (modern, poorly-assembled GDI) and circumstance (might only getting a new long-block).

Lots of opinions on break-in oil changes. Here is a short list of threads you can read.

Here's another one on a replacement Hyundai engine.

I’m a fan of Super Tech synthetic oils

I don't think I'd tempt fate with Supertech in a shoddy Hyundai engine. Agree with the post above: Valvoline Restore and Protect 5W-30 or Mobil 1 ESP 0W-30.

 

[Hirev]

As an aside, I’m a fan of Super Tech synthetic oils and wonder if anyone could weigh-in on the utility of using their conventional variant before migrating to FS (for break-in

I would think when the dealer puts in the new long block the dealer is going to put in what they have in the shop oil tanks. Most of the break in is going to take place in the 1st 500 - 1200 miles. I would not worry about using a conventional conventional oil. They have been using FS in many new cars for a long time. My 2007 corvette factory fill was FS. It is still doing fine.

 

[ChrisD46]

For off the shelf I’d highly recommend Mobil 1 ESP 0w-30 or Valvoline Restore and Protect 5w-30 with OCI 4-5k miles. Would also recommend a premium guard filter such as Carquest premium/EP or microgard select.

My daughter has a 2019 Santa Fe with 90k miles and will be using Mobil 1 Advanced Clean 5w-30 (got it on sale) next OCI before switching to HPL premium plus 5w-30 for as long as we own it

^^This^^ ! These oils along with Mobil 1 5W30 regular or Mobil 1 Extended Performance oils are what I have been running in my 2017 2.4L Sonata . *I believe 5K mile OCI’s are too long in this engine so I use the severe duty schedule usually keeping OCI’s to 3,500 - 3,800 miles and no more than 4,000 miles. I currently have 61,000 miles on the Sonata and with the exception of a little oil consumption I’ve had no issues to date.

 

[Escape08]

What? For a faulty crank sensor and the car needs a new engine? C.mon. the dealer wants $$$ for a new engine. Dealer's not billing you, they're billing Hyundai

 

[snail415]

What? For a faulty crank sensor and the car needs a new engine? C.mon. the dealer wants $$$ for a new engine. Dealer's not billing you, they're billing Hyundai

Let me clarify-

This wasn’t the dealer telling me what I need, but the long track-record of these engines grenading shortly after the crank sensor (doing its job) detected knock. There’s nothing wrong with the sensor on a 50k-mile engine. It’s more than likely the result of a manufacturing process that omitted a proper removal of micro-metal shavings during the CNC process.

And I’m not out-of-the-woods just yet. The service manager actually leaned towards me and said “HMC may ask for receipts of the oil you purchased for your at-home changes. It’s BS. However, given the low miles at 9 years, you stand to get taken care-of.”

Ironically, it’s testimony that I’ve read here on the BITOG forum that compelled me to use Super Tech for so long in my car, and at a conservative OCI. It would be kind-of funny (eventually) if that diligence works against me here; there’s nothing better I could have really done, and the crank sensor certainly isn’t the problem.

Anyhow, I appreciate everyone’s responses.

 

[snail415]

Which oil did you use?


Lots of opinions on break-in oil changes. Here is a short list of threads you can read.

Here's another one on a replacement Hyundai engine.


I don't think I'd tempt fate with Supertech in a shoddy Hyundai engine. Agree with the post above: Valvoline Restore and Protect 5W-30 or Mobil 1 ESP 0W-30.

I reviewed those past threads and believe that was a ‘new-member hazing’ trick. That’s exactly what I was trying to avoid!

 

[hemitom]

^^This^^ ! These oils along with Mobil 1 5W30 regular or Mobil 1 Extended Performance oils are what I have been running in my 2017 2.4L Sonata . *I believe 5K mile OCI’s are too long in this engine so I use the severe duty schedule usually keeping OCI’s to 3,500 - 3,800 miles and no more than 4,000 miles. I currently have 61,000 miles on the Sonata and with the exception of a little oil consumption I’ve had no issues to date.

This is what you want to do . ^^^
Especially in a short tripped vehicle !
in our Hyundai Accent which is generally short tripped the oil gets changed at 3000 miles its currently at 60k and has been trouble free.

 

[goblin]

I'm the other Hyundai guy with a reman engine here, and I went for Motul Break-In 10w40 from FCPEuro.
Here's the oil analysis at 900 miles.

I replaced the dealership's oil with the Motul as fast as I could.
I had an upcoming trip, it was just before Christmas, so my path was literally Pick car with new engine at the dealership > Drive 12 miles to my local Valvoline > Give then the oil in the trunk (they will usually do it with client-provided oil, they have an item in the system for labor only) > Drove 400 miles > small trips for a couple of days > Drove another 400 miles back > Replaced oil.

I asked Chat GPT for the break-in procedure to confirm what I planned on doing (without sharing my plans of cours), the output was 100% what I was about to do anyway, but with interesting details (shift points, rpms, what to do at what mileage).

In my book a remanufactured engine is not a brand new engine (unless they stock those for the warranty repairs for yours). Ai can find the part numbers for new engine replacement kit and remanufactured ones.

I probably went overkill with dedicated break-in oil, but I don't regret it. Given what I see on the oil analysis at 900 miles - I'd say if you don't do anything else - do your first oil change at 1000 miles, not 5000.

If I had to sum it up:
- Always bring the engine to temp, driving (not idling).
- Do not underrev, do not lug the engine.
- Use engine braking with transmission in manual mode.
- Do not overrev.

I drove those whole 900 miles in manual shift mode, never letting the computer decide. It always wants me to coast at 1200rpm, I was always keeping it at at least double that.

Here are a few things you need to know:
- The dealership will not put any special oil for you. If they are one of them shops that only have synthetic, they'll put synthetic in.
- They will not preemptively change a single bolt that is not mentioned in the replacement procedure, just because the engine is out and stuff is accessible. They'll reassemble it with whatever parts need to be moved from the old one. On mine, they put back the old accessory belt and pulleys, even though I offered to give them new ones so they can spare themselves the work of taking the old ones off the old engine.

After you get your car back - drive it, extensively. Listen for new noises. An engine replacement disturbs a lot of things. And the ones working there are not always the brightest.

Your car has only 50k miles, so most of the accessories are in good condition and will last on your new engine. But one way or the other - after you get it back, drive it. A lot. See if anything feels different. An exhaust that is not fully tightened can take hundreds of miles to start farting.

Good luck.

 

[PhilloBeddow]

Let me clarify-

This wasn’t the dealer telling me what I need, but the long track-record of these engines grenading shortly after the crank sensor (doing its job) detected knock. There’s nothing wrong with the sensor on a 50k-mile engine. It’s more than likely the result of a manufacturing process that omitted a proper removal of micro-metal shavings during the CNC process.

And I’m not out-of-the-woods just yet. The service manager actually leaned towards me and said “HMC may ask for receipts of the oil you purchased for your at-home changes. It’s BS. However, given the low miles at 9 years, you stand to get taken care-of.”

Ironically, it’s testimony that I’ve read here on the BITOG forum that compelled me to use Super Tech for so long in my car, and at a conservative OCI. It would be kind-of funny (eventually) if that diligence works against me here; there’s nothing better I could have really done, and the crank sensor certainly isn’t the problem.

Anyhow, I appreciate everyone’s responses.

My son drives a 2019 Optima with the Theta II engine that has the lifetime warranty from a defective design.

It gave the same P01386 code so he had it towed to the dealer and they fixed it at no charge under warranty.

It was the sensor.

FYI, From what I can gather, the P01386 diagnosis uses a factory test jig with a dial gauge to measure the crankshaft bearing play rather than strip the engine. It didn’t take long for the dealers technician to diagnose and he was back on the road soon after.

Good luck.

Edit- to clarify, the dial gauge is threaded into the plug hole and piston crown travel is measured as the crank turns. If it follows a smooth path, the bearings are deemed to be OK. If there’s a step in the measured travel, the bearings are suspect.

 

[CarLuver]

Kirkland 5/30 is all that was use in the Tucson. Use it in everything i have .

 

[snail415]

I'm the other Hyundai guy with a reman engine here, and I went for Motul Break-In 10w40 from FCPEuro.
Here's the oil analysis at 900 miles.

I replaced the dealership's oil with the Motul as fast as I could.
I had an upcoming trip, it was just before Christmas, so my path was literally Pick car with new engine at the dealership > Drive 12 miles to my local Valvoline > Give then the oil in the trunk (they will usually do it with client-provided oil, they have an item in the system for labor only) > Drove 400 miles > small trips for a couple of days > Drove another 400 miles back > Replaced oil.

I asked Chat GPT for the break-in procedure to confirm what I planned on doing (without sharing my plans of cours), the output was 100% what I was about to do anyway, but with interesting details (shift points, rpms, what to do at what mileage).

In my book a remanufactured engine is not a brand new engine (unless they stock those for the warranty repairs for yours). Ai can find the part numbers for new engine replacement kit and remanufactured ones.

I probably went overkill with dedicated break-in oil, but I don't regret it. Given what I see on the oil analysis at 900 miles - I'd say if you don't do anything else - do your first oil change at 1000 miles, not 5000.

If I had to sum it up:
- Always bring the engine to temp, driving (not idling).
- Do not underrev, do not lug the engine.
- Use engine braking with transmission in manual mode.
- Do not overrev.

I drove those whole 900 miles in manual shift mode, never letting the computer decide. It always wants me to coast at 1200rpm, I was always keeping it at at least double that.

Here are a few things you need to know:
- The dealership will not put any special oil for you. If they are one of them shops that only have synthetic, they'll put synthetic in.
- They will not preemptively change a single bolt that is not mentioned in the replacement procedure, just because the engine is out and stuff is accessible. They'll reassemble it with whatever parts need to be moved from the old one. On mine, they put back the old accessory belt and pulleys, even though I offered to give them new ones so they can spare themselves the work of taking the old ones off the old engine.

After you get your car back - drive it, extensively. Listen for new noises. An engine replacement disturbs a lot of things. And the ones working there are not always the brightest.

Your car has only 50k miles, so most of the accessories are in good condition and will last on your new engine. But one way or the other - after you get it back, drive it. A lot. See if anything feels different. An exhaust that is not fully tightened can take hundreds of miles to start farting.

Good luck.

Fantastic insights. Appreciate you taking the time to share!

 

[snail415]

My son drives a 2019 Optima with the Theta II engine that has the lifetime warranty from a defective design.

It gave the same P01386 code so he had it towed to the dealer and they fixed it at no charge under warranty.

It was the sensor.

FYI, From what I can gather, the P01386 diagnosis uses a factory test jig with a dial gauge to measure the crankshaft bearing play rather than strip the engine. It didn’t take long for the dealers technician to diagnose and he was back on the road soon after.

Good luck.

Edit- to clarify, the dial gauge is threaded into the plug hole and piston crown travel is measured as the crank turns. If it follows a smooth path, the bearings are deemed to be OK. If there’s a step in the measured travel, the bearings are suspect.

Thank you for sharing this. Let’s hope whatever the diagnosis, it’s thorough and honest.

 

[Mainia]

Hi all,

First post here on the forum. I have a 9 year-old Hyundai Sonata (2017) that I purchased new. It only has 50k miles at time of this post. While I changed oil every 5k miles, I never had to research all of the gremlins this engine is known-for. It’s been a solid car for most of our time with it, and it saw nothing but short trips and not even work commutes. Given the low mileage, I’m assuming we just got lucky for nearly a decade and were due for the inevitable. Thank goodness it’s still under warranty.

For the first time ever last week, the car went into limp-mode. I confirmed it threw the 1386 code (crank sensor). Car is now at the dealer, and so-far the service department is signaling that a new motor is likely.

If it pans-out that way, I’d appreciate recommended break-in oil types/viscocity/schedules specific to this type of engine (modern, poorly-assembled GDI) and circumstance (might only getting a new long-block). If you’re experienced with this engine and any successful mitigation strategy, I’d appreciate your take. We need this car to last as long as possible.

As an aside, I’m a fan of Super Tech synthetic oils and wonder if anyone could weigh-in on the utility of using their conventional variant before migrating to FS (for break-in). If I’m simplifying the matter, or if this has been covered at-length, please forgive my ignorance. I’d like input and perspective as current as possible. Thanks in advance.

DEMAND an long block. They will never get all the crap out of the cylinder head oil pathways. What's left in the cylinder head will contaminate the new motor. Tell them your keeping the car for another 10 years. You want a proper fix, not a mickey mouse fix with a contaminated head. And NO, tanking it won't guarantee the metal flakes are gone.That is if it is more damaged then just doing a rod bearing redo.

 

[Mainia]

My son drives a 2019 Optima with the Theta II engine that has the lifetime warranty from a defective design.

It gave the same P01386 code so he had it towed to the dealer and they fixed it at no charge under warranty.

It was the sensor.

FYI, From what I can gather, the P01386 diagnosis uses a factory test jig with a dial gauge to measure the crankshaft bearing play rather than strip the engine. It didn’t take long for the dealers technician to diagnose and he was back on the road soon after.

Good luck.

Edit- to clarify, the dial gauge is threaded into the plug hole and piston crown travel is measured as the crank turns. If it follows a smooth path, the bearings are deemed to be OK. If there’s a step in the measured travel, the bearings are suspect.

I don't think it is a crankshaft, the problem are the rod bearings. They could throw in just rod bearings if they caught it early.

 

[dogememe]

I wouldn't worry about it and just change it at 1k miles then continue on with your typical 5k OCI. I don't think any type of oil can resolve a mechanical problem or design defect.

 

[tired]

Kirkland 5/30 is all that was use in the Tucson. Use it in everything i have .

I think that's probably why you developed the oil burning issue. Better oils seem to prevent it, despite the design issue. Glad you got a new engine though. (It's nice if you use the reply feature btw.)