Genesis G90 2018 transmission issues.

[Ann L.]

When I had my 2018 g90 5.0 in this week I advised it does not always start. They checked everything and battery - all is OK. Today, again, start, all the lights come on, wait, the engine does not start. I am winning the lottery twice.

Riley - I disagree with you. If you have a v8 between the years of 2017 and 2018 - (don't know about 2019). I believe there is a greater than 85% chance the coolant will leak and the car will overheat due to faulty o rings. It's just a matter of time, mine took 10 months. I would love for you to prove me wrong so all the owners out there don't have to carry coolant and a funnel.

 

[Gene2]

Sorry to say way to many 5.0's are having this problem to be like winning any thing.
When mine went out, had to wait for new o ring to be made, as o ring one here in the country
was already used. Wish my odds of winning the lottery was that good

 

[glennk]

Is there an associated TSB for the '15 Genesis V8?

 

[Mcc]

It's just a matter of time, mine took 10 months. I would love for you to prove me wrong so all the owners out there don't have to carry coolant and a funnel.

How do you prove that something will not happen?

 

[jimmy buoy]

Just got around to checking my coolant levels (for the first time since having the car - 3/5yrs now) and the main rad has coolant but it isn't covering the port that goes to the overflow tank - could use a top up. Checked the overflow tank's dipsy dipstick and couldn't see any fluid but wasn't sure if that goofy stick ever shows fluid. All the same it seemed dry. Using a flashlight after dark I did see the side of the overflow tank with the L and F markings, but it also didn't seem to show ANY fluid in it at all. YIKES! Not sure if it ever had fluid or not, but I'll be topping it up after getting antifreeze tomorrow. Then I'll be watching the level daily for a while to see if there is a drop.

Not sure where it all went if it was there in the first place. No coolant smells ever. No signs of coolant leaks either. Car temp levels have always been nominal.

Glad this post started so I had the push to actually check the levels for myself!

 

[Ann L.]

Where do you live. Does your heater work? How many miles on the vehicle. Mine never ran hot until the engine overheated. The dealership said you couldn't see the fluid leak because it was in the back of the engine.

 

[onexcite]

Just got around to checking my coolant levels (for the first time since having the car - 3/5yrs now) and the main rad has coolant but it isn't covering the port that goes to the overflow tank - could use a top up. Checked the overflow tank's dipsy dipstick and couldn't see any fluid but wasn't sure if that goofy stick ever shows fluid. All the same it seemed dry. Using a flashlight after dark I did see the side of the overflow tank with the L and F markings, but it also didn't seem to show ANY fluid in it at all. YIKES! Not sure if it ever had fluid or not, but I'll be topping it up after getting antifreeze tomorrow. Then I'll be watching the level daily for a while to see if there is a drop.

Not sure where it all went if it was there in the first place. No coolant smells ever. No signs of coolant leaks either. Car temp levels have always been nominal.

Glad this post started so I had the push to actually check the levels for myself!

Seem like you got a leak somewhere. Mine is the same when I caught it before the engine overheat.

 

[Taxexempt]

Got a gallon of this to keep handy.

 

[jimmy buoy]

Where do you live. Does your heater work? How many miles on the vehicle. Mine never ran hot until the engine overheated. The dealership said you couldn't see the fluid leak because it was in the back of the engine.

Live in Ontario Canada and yes, the heater works fine. 60,000 Killometers (40,000 Miles) in the 3.5yrs Ive had it. I would think if coolant was leaking on top of the engine but underneath the intake manifold it might not be seen but you sure should be able to smell it coming off the top of a hot engine. No such odour, so I'm going to do a top-up and watch it like a hawk!

 

[vasy]

Coolant evaporates slowly in most cars' cooling system where the overflow tank is not airtight by design. It's possible for a 3.5-year-old car with 40,000 miles to lose this much coolant by evaporation. jimmy buoy's car is not a G90 so I don't know its cooling system. I'm not sure if G90's system is a closed system (completely airtight) or not. In others with totally closed cooling system that prevents/minimizes evaporation, the radiator itself doesn't have a cap. A pressurized cap is installed on the overflow tank. In such a system the liquid coolant does not have much room to evaporate into because it's not connected/exposed to ambient air. In G90, the cap on the radiator is of course airtight; the black plastic cap on the overflow has a very tight rubber gasket. It takes a lot of muscle to screw on this cap and that makes me think this overflow is airtight. If the overflow tank does not have a vent hole then the entire cooling system should be airtight and does not permit much evaporation. Once again I'm talking about G90 not Hyundai Genesis.

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[Riley2323]

How do you prove that something will not happen?

That is a quote from Zero Dark Thirty!

 

[jimmy buoy]

Coolant evaporates slowly in most cars' cooling system where the overflow tank is not airtight by design. It's possible for a 3.5-year-old car with 40,000 miles to lose this much coolant by evaporation. jimmy buoy's car is not a G90 so I don't know its cooling system. I'm not sure if G90's system is a closed system (completely airtight) or not. In others with totally closed cooling system that prevents/minimizes evaporation, the radiator itself doesn't have a cap. A pressurized cap is installed on the overflow tank. In such a system the liquid coolant does not have much room to evaporate into because it's not connected/exposed to ambient air. In G90, the cap on the radiator is of course airtight; the black plastic cap on the overflow has a very tight rubber gasket. It takes a lot of muscle to screw on this cap and that makes me think this overflow is airtight. If the overflow tank does not have a vent hole then the entire cooling system should be airtight and does not permit much evaporation. Once again I'm talking about G90 not Hyundai Genesis.

Even though my 15 Hyundai Genesis is not a Genesis G90, I don't think that Hyundai Motors (the manufacturer of both) would have two completely different 5.0 V8 Tau engines. My overflow cap is the same as you've described, with a pressurized cap that has a "very tight rubber gasket". It also has a separate "ribbon" type plastic dip stick with horizontal slots which will indicate the fluid level by retaining fluid in the slots after being removed. It's a bit difficult to read, but easier in low light conditions using a flashlight to see where the fluid filled slots end. You can see the tank, but it's really difficult during the day to see the fluid level. I find it's easier to see in the evening using a flashlight to determine the level between the "L" and "F" lines.

 

[Riley2323]

When I had my 2018 g90 5.0 in this week I advised it does not always start. They checked everything and battery - all is OK. Today, again, start, all the lights come on, wait, the engine does not start. I am winning the lottery twice.

Riley - I disagree with you. If you have a v8 between the years of 2017 and 2018 - (don't know about 2019). I believe there is a greater than 85% chance the coolant will leak and the car will overheat due to faulty o rings. It's just a matter of time, mine took 10 months. I would love for you to prove me wrong so all the owners out there don't have to carry coolant and a funnel.

I reread the entire thread. I have the 17 Ultimate 5.0. Just went over 36K.

All my points about winning the negative lottery also involve having it happen at an in opportune time and to such a level that it is catostrophic to the car and perhaps dangerous, and yes I was talking about the entire new car population to another poster’s point. The stars would have to be aligned for it to all go wrong in such a way to make it worse than getting a flat tire from hitting a pot hole.

I will keep my eye on the coolant and temperature gauge.

You wonder how much QC would be on the o-ring part during assembly. Did they run out of O-rings and grab from another line? Was it faulty blue resin? Is the ring perfectly fine but there is too much angular movement causing it to get pinched and rupture and they went with what looks like a bigger one?

These posts are making me feel like I will win a race getting to November 17th.

My issues have all been road and me related:

Me:
-Screwdriver in back pocket caused 1/2” hole in driver seat.
-Lawnmower part on shelf fell when getting leaf blower....2 dents on hood.
-garage door scratched back bumper due to having one inch to spare when it is in garage.

Road:
-pothole = new tire
-nail = repaired tire
-Pothole = new tire and rebuilt front passenger wheel for about $3k of repairs including tire.
-Brakes excessive wear, had them repaired twice...pads once and rotors turned...might be me.
-rock on radar cover cracked it.
-rock = new windshield.

The second pothole was about 10 days of being without the G90, so that is what I meant about stars being aligned to have o-ring being a worse event then a flat tire.

Good luck on the “not starting” issue. Couple of threads on that. Make sure it is not a brake pedal not being depressed enough. Sounds like you are due for an easy issue Anne.

I also think I would trade your o-ring issue for all of my repairs.

 

[ctrcbob]

I reread the entire thread. I have the 17 Ultimate 5.0. Just went over 36K.

All my points about winning the negative lottery also involve having it happen at an in opportune time and to such a level that it is catostrophic to the car and perhaps dangerous, and yes I was talking about the entire new car population to another poster’s point. The stars would have to be aligned for it to all go wrong in such a way to make it worse than getting a flat tire from hitting a pot hole.

I will keep my eye on the coolant and temperature gauge.

You wonder how much QC would be on the o-ring part during assembly. Did they run out of O-rings and grab from another line? Was it faulty blue resin? Is the ring perfectly fine but there is too much angular movement causing it to get pinched and rupture and they went with what looks like a bigger one?

These posts are making me feel like I will win a race getting to November 17th.

My issues have all been road and me related:

Me:
-Screwdriver in back pocket caused 1/2” hole in driver seat.
-Lawnmower part on shelf fell when getting leaf blower....2 dents on hood.
-garage door scratched back bumper due to having one inch to spare when it is in garage.

Road:
-pothole = new tire
-nail = repaired tire
-Pothole = new tire and rebuilt front passenger wheel for about $3k of repairs including tire.
-Brakes excessive wear, had them repaired twice...pads once and rotors turned...might be me.
-rock on radar cover cracked it.
-rock = new windshield.

The second pothole was about 10 days of being without the G90, so that is what I meant about stars being aligned to have o-ring being a worse event then a flat tire.

Good luck on the “not starting” issue. Couple of threads on that. Make sure it is not a brake pedal not being depressed enough. Sounds like you are due for an easy issue Anne.

I also think I would trade your o-ring issue for all of my repairs.

With all those things happening to you, I think you should get a job writing Country Music.

 

[vasy]

About this defective o-ring in 5.0 engines, I think if you keep this car (V8 only) long enough the coolant leak will eventually happen, just a matter of time. Why? This o-ring is defective. They have an updated/improved o-ring to replace the original version. I have the 5.0 and I'll do my best to find this leak before warranty expires. I always carry a gallon of diluted Hyundai coolant in my trunk when I take this car for a road trip even before learning about this issue. From pictures in the TSB, slowly leaked coolant (greenish color on the recessed aluminum engine part) stays on the top of the engine due to the recessed contour structure. So it won't drip down to the lower part of the car and to the garage floor where we can spot. Even if it does drip down, the coolant will stay on the plastic bottom cover instead of getting to the floor for us to see. So all 5.0 owners should check coolant level on a regular basis and hope this problem does happen to our cars before warranty runs out. Don't hope it won't happen because most likely it will, eventually.

Ok, 5 months after my own posting my car started to act up. It lost about 1/2 inch of coolant in the overflow tank for about 20 minutes of city driving. I never let the overflow tank to get empty so my car never overheated. Took the car to the dealer with a printed copy of TSB 18-AT-017-1. Had to wait for them to order parts. 12 days later the job was done and my car is whole again. Very pleased that I caught this problem before my planned 5000 mile road trip in November. I also found a much smaller coolant leak at the thermostat assembly (where the lower radiator hose connects to the top of the engine). Told them about it and they replaced the entire thermostat assembly. I've had this car since January 2018 but only put on 6800 miles so far. This is my first service visit so they also changed oil and cabin air filter.

 

[ogogolby]

Do you mind sharing with us what kind of issues you've had? Thanks.

It's quite a list and the vehicle is going back again tomorrow:
New -front end way out of alignment, steering wheel 10 degrees to the left, 4 attempts to fix a wind leak -no luck, road force balancing required replacement of 2 front tires at 5K miles, car still feels nervous on the road. Now, sunroof and broken trim.

 

[vasy]

It's quite a list and the vehicle is going back again tomorrow:
New -front end way out of alignment, steering wheel 10 degrees to the left, 4 attempts to fix a wind leak -no luck, road force balancing required replacement of 2 front tires at 5K miles, car still feels nervous on the road. Now, sunroof and broken trim.

Thanks for sharing. About sunroof, I don't like it and I don't use it. Only opened it twice for testing after purchasing the car. My thinking is, if it's very seldom opened, debris and dirt won't get in the track area to clog drain holes. Some folks complained about not having a panoramic sunroof in G90 but I think it's a blessing. Got a 2019 G80 as a loaner car while they worked on my G90 last week. This G80 has a huge sunroof. The entire outside roof (except the edge) is made of materials that a magnet won't stick. I don't want to be in a car like that if getting into a major accident on highway. Hope they fix your car this time.

 

[Bernster]

Don't have a transmission problem. But I wanted to mention that Coconut Creek Hyundai in South Florida has excellent new car prices and leases and great service.

 

[new_G80_owner_KC]

New TSB for Transmission Problems - 19-AT-014HG

 

[Mike734]

Had my hard shifting 2018 G90 serviced toda; referenced that service bulletin. They said a solenoid was "a little high" and they reset the learning. I drove it for a half a block and it seemed better. I'll drive it cold tomorrow and report back.