5.0 Coolant Leak

[G-277981]

No personal experience, but there have been issues with newer 5.0 models where an O-Ring in that exact spot on a coolant pipe that goes to the transmission begins to leak. I think Hyundai has a service bulletin for the issue which involves taking the manifold, replacing the O-Ring with an improved one which seals everything again. You don't want to ignore since low coolant levels could cause an overheat and engine damage.

Here's a thread on this issue... (G90 issue, but the same 5.0 engine so who knows)

Genesis G90 2018 transmission issues.

Thanks @ jimmy bouy. Our 2018 G90 just overheated last week. Only 22K miles on it. Full reservoir, no apparent leak, but odor of coolant under hood.I referred to this thread and your mention of Technical Service Bulletin TSB 18-AT-017 - Coolant leak at ATF warmer connection helped immensely. I printed it out, made an appointment with the dealership, left it with the service mgr. Sure as shootin', it was exactly the problem. They fixed it under warranty so I can't give the figures on cost. Thanks. Car is back running cool, in the blue.

 

[skipgen]

Thanks @ jimmy bouy. Our 2018 G90 just overheated last week. Only 22K miles on it. Full reservoir, no apparent leak, but odor of coolant under hood.I referred to this thread and your mention of Technical Service Bulletin TSB 18-AT-017 - Coolant leak at ATF warmer connection helped immensely. I printed it out, made an appointment with the dealership, left it with the service mgr. Sure as shootin', it was exactly the problem. They fixed it under warranty so I can't give the figures on cost. Thanks. Car is back running cool, in the blue.

My Indie shop did the work on mine. I got the washers from Hyundai parts deal (~ $5). Took them about 3-4hrs and $275 to take care of it. Mine wasn't leaking that badly - my temps stayed normal, but I was topping off coolant about every 2 weeks.

 

[carguy75]

Damn. I did not know our cars had a coolant leak issue. I just ordered new o-rings as recommended by the TSB and new intake manifold gaskets to head this problem off at the pass. I guess I can try to clean my intake valve stems at the same time with some CRC carbon cleaner since they will be exposed with the intake manifold removed.

Thank for the heads up people.

Part numbers for the coolant pipe o-rings from the coolant pipe TSB.

 

[glennk]

When I have the transmission serviced, I'll have the TSB performed.

This is EXACTLY why I love this site. Getting the information and fixes out there!

 

[xmike305]

Damn. I did not know our cars had a coolant leak issue. I just ordered new o-rings as recommended by the TSB and new intake manifold gaskets to head this problem off at the pass. I guess I can try to clean my intake valve stems at the same time with some CRC carbon cleaner since they will be exposed with the intake manifold removed.

Thank for the heads up people.

Part numbers for the coolant pipe o-rings from the coolant pipe TSB.
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Brother where can I find the intake manifold gasket just got this problem now and can't seem to find gaskets anywhere is there a part number you can share ?

 

[G-8477]

Brother where can I find the intake manifold gasket just got this problem now and can't seem to find gaskets anywhere is there a part number you can share ?

I bought mine at the dealer.... Wasn't too expensive but you need 8 of them.

 

[xmike305]

I bought mine at the dealer.... Wasn't too expensive but you need 8 of them.

Thanks brother I saw it was sold by 1’s just ordered 8 of them since my dealer nearby only had 2 left . I have them coming in this weekend to fix her up I appreciate the response! For anyone in the future needing this fix done the Part No is 28313-3F400

 

[Bryandowen]

I know this is an old thread, but I'm researching an issue I'm having. I'm not noticing any overheating and haven't checked my coolant level, but I've got a burnt coolant smell in the passenger cabin. I'm wondering if the issue described in this thread might result in a smell inside the car. I also notice that my windshield gets hazy over time and I have to wipe it clean every few months, which could be related to the smell.

 

[Dtinnc]

I know this is an old thread, but I'm researching an issue I'm having. I'm not noticing any overheating and haven't checked my coolant level, but I've got a burnt coolant smell in the passenger cabin. I'm wondering if the issue described in this thread might result in a smell inside the car. I also notice that my windshield gets hazy over time and I have to wipe it clean every few months, which could be related to the smell.

I suppose it is possibly related... But coolant level has to be dropping, albeit slowly. The absolutely only way to prove the issue is to pressurize the coolant system and watch for slow leaks. If the engine is cool, you will eventually see a drip near the rear of the engine. Hot engines vaporize the coolant before it can drip, so it's never visible.

My car would lose coolant over a week or so with minimal driving.

Very tedious repair due to the amount of things that need to be removed. I replaced the entire "connector" body and total cost was $35 or so from the dealer.

 

[Bryandowen]

I asked the shop to look into this when I took it for service last week and they confirmed there is a small leak *somewhere*. I couldn't leave my car with them for another day or two so they weren't able to get to the bottom of it. I'm worried it'll be the heater core in the cabin and they'll have to tear apart my entire dash and it'll cost a mint and start rattling and squeaking and never be the same. :-\

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[Dtinnc]

I asked the shop to look into this when I took it for service last week and they confirmed there is a small leak *somewhere*. I couldn't leave my car with them for another day or two so they weren't able to get to the bottom of it. I'm worried it'll be the heater core in the cabin and they'll have to tear apart my entire dash and it'll cost a mint and start rattling and squeaking and never be the same. :-\

Harbor Freight has a higher end pressurizing kit for about $129 that I used to detect the leak. May be a worthwhile expense rather than back and forth to shops. Pressurize to between 13-17 psi and then walk away for fifteen minutes. Take a picture of the pressure gauge so that you can detect even a slight change when you return