[Sparklander]

There have been reports of PHEV owners getting their oil changed on time, and their oil still looks to be extremely contaminated with gasoline.

I know GDI engines have routinely had this problem, but it seems to be pronounced with PHEV's. The problem stems from the ICE not getting warmed up sufficiently while the car is in EV mode.

Every car with an internal combustion engine needs to be driven a sufficient distance at a sufficient speed to burn off the contaminants in the oil from the fuel.

The solution would be to drive the vehicle in ICE only mode (by not charging the EV battery) every few weeks. Here is a sample of the oil drained from a PHEV at the normal service time (taken from FB post). To allow the extreme dilution of the oil would greatly reduce the longevity of the engine.

 

[Sparklander]

I don't have any axe to grind against Kia. I own the Sportage Hybrid. Just relaying information that a few other PHEV owners have noticed after changing their oil at 5K miles. I am sure any PHEV owner would notice the oil dilution problem by merely checking the oil level on the dipstick, but will they even look?

The message is simple, if you own a PHEV keep an eye on the oil. But you should do that with any car other than a pure EV.

 

[Sparklander]

I don't think it's a PHEV issue, but rather an issue with the 1.6L Smartstream engine. I've seen a lot of news articles in Korean news with that issue

I agree, but the problem is more pronounced in the PHEV because of how much less the ICE works.

 

[Sparklander]

Without being able to smell that oil sample, it's hard to tell if it's actually fuel or simply moisture in the oil. In colder climates (where I live) many short trips can result in your oil looking like that due to moisture (condensation due to temperature). But a short road trip to get the engine up to temperature will burn the moisture off fairly quickly. You can see in the link below what oil can look like when this happens.

https://www.techenomics.net/2014/01/water-in-oil/

Thank you for the response. Does the PHEV engine really ever get hot enough to burn off the contaminants if the owner only uses it in EV mode around town? I would not want either gasoline or water in the oil for a prolonged period of time.

Time will tell whether the 1.6T in the PHEV or the HEV will last longer. It's too early to tell.

 

[Sparklander]

Doesn't the Tucson PHEV have the exact same engine? It's been out for a while.

It does. The first Tucson PHEV came out as a 2022 Model, so it has been on the streets for less than two years.

Hyundai is discontinuing its Santa Fe PHEV for 2024. Not sure of the reason. No word on the Kia Sorento PHEV.