In March 2023, my wife's 2016 Kia Sorrento 3.3 V6 had only 120,000 miles on it when we had to take it into the dealership after I noticed a sweet smell from the AC vents, like "coolant". We took it in just to be safe and for peace of mind, only to be told that it seemed as if the head gasket was about to fail.

I held off on any repairs until I could research the vehicle further. I couldn't believe that a vehicle that has been serviced regularly and has never been abused could have a head gasket failure. I've never experienced anything like this with any of my 20+ vehicles owned throughout the years.

After extensive research using Kia forums, looking up class action lawsuit history, and numerous complaints about "KNOWN FAILURES" with the head bolts backing out/stripping/failing leading to the head gasket failure/engine failures.

Looks like Kia went the cheap route and is only covering 4-cylinder engine failures through a filed class action lawsuit but hasn't addressed the ongoing 3.3 V6 failures.

I refuse to pay $9-10k to have a used/refurbished motor replaced that will probably experience the same failure with no fault of our own.

WAITING ON KIA TO OWN THIS BS........Waiting.......Waiting......

We are the original owners of a 2016 Sorento SX+ with the 3.3L V6 engine. Car has always had its regular maintenance on time and undercoated. It is in pristine shape. Without warning or any warning lights on the dash, no heat was coming out of the heater. The fluid in the radiator was low, so I topped it off. In a few days the heater stopped working again and the car overheated without warning. Thinking it was a thermostat problem, the thermostat and water pump was replaced ($1000). The next day the heater stopped working again and I could see bubbles of air coming into the coolant reservoir.

Took to a Kia dealer for a diagnosis and was told the head gasket(s) were gone and coolant was leaking into the cylinders. Was told the only option was a new engine or a used engine at a cost to me of upwards of 10k(can). Mechanics at Kia had seen this before and told us that Kia has known about incorrectly manufactured head bold threads in the aluminum engine block of the 3.3 V6 engines. Kia does not have a recall or warranty on this item. This is most definitely a manufacturing defect and should be covered by Kia. This problem is a ticking time bomb and has very little warning that it is happening and can leave you stranded on the side of the road or possibly leading to an engine stall causing loss of control.

Research online shows a large number of exactly the same lose head bolt issue on the 3.3L V6 engines to the point where its such a large problem that someone (https://www.huhnsolutions.com/) has a specific kit to fix this exact problem! I am now out a vehicle and refuse to pay over 10k for someone else to fix it. So very disappointed in Kia. I had though the engine troubles with earlier models like the Sonata were behind them. This was not a cheap car! Will NEVER buy a Kia or Hyundai again! Stay Stay away from these cars.

When my Sorento started overheating I took it to a local shop who diagnosed the head gasket, but didn't want to touch it. ($50) The Hyundai dealership said over the phone they could service Kias, but then told me that they would just condemn the whole motor but not do the work to replace themselves ($150). A different local shop agreed to take on the head gasket job with an open estimate, in case the heads were warped or something-and they discovered the loose head bolts ($1320). So then towed again down to the closest Kia dealership -80 miles...for them to tell me-after having the car for nearly 2 weeks- that the original estimate ($7,458.79) is no longer valid because KIA USA requires a complete full assembly of the original block so now the price is $11,893.11. I am livid. I am paying that outrageous cost plus the $1320 just to find that the head bolts were stripped is why my repair numbers are higher than average.

According to KIA, if I were the original owner everything would be under the powertrain warranty. 2nd owner, but 8 months.

I bought our 2016 Sorento 0n 02-23-2023 from a very respected dealership where I live. It had a little over 117,000 miles and I bought the extended warranty that day. The warranty is through AUL. It had one previous owner, and maintenance was performed either early or on time every time. There was no major issues with this vehicle.

About a month and a half of driving, with no warning lights nor any indication of a problem, about a block from the dealer, the temp gauge pegged in the red. The warranty required that if you are within a certain mileage from the dealer you must take it there so I did. They said that it was low on antifreeze, they put some in and it drove fine, no issues, however they needed to find out where it went because it was not on the engine or the ground. Another couple of weeks and they said it was a blown head gasket.

Another week the adjuster with AUL checked it out and the work was approved. When they got into it they discovered the head bolt(s) were stripped. It was at this point AUL said we wont pay for that. In the contract it says if a bolt, nut etc fails it's not covered. The dealer told me it would cost $11,000.00 dollars which there is no way that I can do that.

At least the dealer is working to figure something out but I am in a tight schedule and have to have a solution and it fixed by the first of July.

KIA has a serious problem and as far as I have been able to research this is a problem they have known about this for some time and so far have not addressed it. This a serious problem with this particular engine which could lead to a catastrophic failure.

We purchased a used 2016 Kia Sorento from South Trail Kia in 2019. The vehicle had been serving us well and we always kept it well maintained and never had any issues with the vehicle.

On July 6, 2022, we were returning back to our home from a road trip when suddenly, the vehicle started to overheat out of nowhere. I opened the hood to find the coolant bubbling in the reservoir and I noticed traces of radiator fluid above the radiator cap on the hood of the car. Thinking that perhaps the seal on the radiator cap was bad, I immediately found a replacement, topped up the coolant but noted that the vehicle temperature gauge continued to fluctuate wildly. On July 7, first thing in the morning, I immediately brought the vehicle to the nearest mechanic to my home a block away.

You can see their assessment process attached below. Initially, they though perhaps there was an external leak in the system. As this was not found to be the case, they deduced it was a blown head gasket. Upon taking the head apart, they noted that 2 head bolts on 2 separate cylinder heads were "so loose that a child could loosen them by hand". I was notified of this on July 11. As you well know, this is not something that could simply occur during normal wear and use. As noted in the mechanic's notes, he specifically points out that it is likely a "manufacturer's defect", perhaps due to the head bolts being overtightened beyond recommended torque during the manufacturing process. As such, this would be a latent defect in the product sold that was not disclosed to the consumer. My mechanic stated he has "never seen anything like this" in his career.

The associated cost as per my mechanic is outlined in the other document provided (minus the costs associated with changing spark plugs). The Kia recommended fix in this situation is also replacement of the lower block or replacement of the engine altogether as the threads in the lower block are now completely stripped. Note that the cylinder heads were not warped or needing to be machined suggesting that this was probably not due to overheating, but as stated, a likely manufacturer's defect.

In any case, after further investigation into this issue doing research online, I have across a multitude of cases reported of customers complaining of almost identical situations.

Kia would do NOTHING about this because it was no longer under warranty. This defect is the "perfect storm" of a problem for a vehicle. Where the problem is completely undetectable until usually only after the warranty has passed. But it causes problems soon enough that it is not worth scrapping the vehicle but also disastrously expensive to fix.