Check engine light O2 sensor problem

I have a 2014 R spec genesis now with about 27,000 miles on it. During last summer when returning from a 2,400 mile road trip the check engine light came on and after some time at the dealership they replaced the O2 sensor and the car ran fine until this last weekend when again on a road trip the check engine light came on. We pulled into the nearest Hyundai dealer and again it is the O2 sensor, but they didn't have one so the rest the computer and sent me on my way a few days later on our way home the check engine light came on again. My home dealership had ordered the part for me.

Thinking about this I think that the problem is caused exhaust soot from driving at a constant speed on the highway because after the light came on during the trip home I got onto the accelerator hard a few times and the car produced a bunch of smoke.

Has anyone had a problem with o2 sensors?

Why would the exhaust soot up driving down the highway at 75=90 MPH?

I don't recall any reports of O2 sensor failures on this forum. That is something that usually does fail at some point, but I wouldn't think it would fail at 27K miles.

Took the car to the dealer today so they could replace the O2 sensor. Guess what they ordered the wrong one so they have to order the correct one and I get to take it back. Took them 45 minutes to find out they ordered the wrong part and had no interest in finding out what is causing the same O2 sensor to go out 2 times in under 30K.

oklawall said:

I have a 2014 R spec genesis now with about 27,000 miles on it. During last summer when returning from a 2,400 mile road trip the check engine light came on and after some time at the dealership they replaced the O2 sensor and the car ran fine until this last weekend when again on a road trip the check engine light came on. We pulled into the nearest Hyundai dealer and again it is the O2 sensor, but they didn't have one so the rest the computer and sent me on my way a few days later on our way home the check engine light came on again. My home dealership had ordered the part for me.

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Has anyone had a problem with o2 sensors?

Why would the exhaust soot up driving down the highway at 75=90 MPH?

Click to expand...

I've had the Check Engine light come on in my 2013 R-Spec three times.

The first time it happened was just a day before I had scheduled my first oil change at the dealer. They told me that the Check Engine light was due to a spurious code that they cleared. They also only put 5 qts of oil in the engine after the oil change. That's the last time they saw my car. That was Dec 2013 @ 3000 mi.

The second time it happened was June 2014 @ 4300 mi. It was due for a 6 month oil change so I took it to a dealer to diagnose the Check Engine light and change the oil. But this time, I knew what the trouble codes were. I had an OBDLink MX Bluetooth code reader in the OBD port. The trouble codes were: P2097, Post catalyst fuel trim system too rich - bank1 and P2099, Post catalyst fuel trim system too rich - bank2. I was able to show the service advisor a screen shot from my phone that showed the codes. Well, they claimed that the reason for the Check Engine light was the K&N air filter I had installed - it was too restrictive, they said. I was not in the mood for an argument, so I let them install an oem air filter and put my K&N in the trunk. At least they put the correct quantity of oil in the engine after the oil change.

The third time with the Check Engine light was July 2014 @ 5050 mi. I took it back to the same dealer who had told me it was my K&N air filter's fault. I had the same trouble codes this time - P2097 & P2099. This time they consulted with their corporate technical resources and decided that the O2 sensors needed to be replaced. They were not in stock and had to be ordered. A week later they replaced two O2 sensors. I asked if I could put my K&N filter back in now and he just gave me a funny look and nodded OK.

Since the O2 sensors were replaced I've had no more Check Engine lights, but I've only drive another 1000 mi since. I still keep my code reader in the OBD port.

First off - Oiled air filters do have a history of causing O2 Sensor and other sensor issues. Many people will get upset that I even say this - but it's fact. Not saying it was your particular issue but it is well known in the automotive engineering world.

My 2014 R Spec lit a MIL light when I was on my first trip. She had about 1300 miles when it came on. Honestly I figured I probably didn't tighten the gas cap so I didn't worry much. I kept on my vacation to the Grand Canyon. Two days (200 miles about) later the MIL went back off. Car always ran fine.

When I got home I plugged in my scan tool. It was O2 sensor. I left the code without clearing and figured I would take it to the dealer when I get around to it. Light is still off and the car has 4700 miles on it now.

Eventually I guess I will get to a dealer and have a look. But it runs fine and no light again.

Note - same as yours, mine occurred on a long highway drive. But I drive 160 miles round trip to and from work each day. So the fact that the MIL light has not come on again makes me think it was just an annomoly. Although I guess it could be that under specific circumstances the engine "loads up" and needs to be floored to clear it out?? Not sure.

I have a 2015 R-Spec with 15,000 miles on it. The CEL gas come on twice in two weeks with the same bank 2 code. It goes back off after a day or two. Local dealer went with, "It happens" on those models. Have it checked at the oil change.

Has anyone replaced O2 sensors on 3.8L? Can you send pics of location on both sides of engine? Any luck with aftermarket O2 sensors, Hyundai’s are crazy expensive.