Hello, how are you doing?
I’m from Brazil and I have an automatic Hyundai HB20 that has a 1.6 Gamma Engine with 26000 miles (F4FA/F4FC) and it’s making a whining noise around 1500RPM, it only happens when the car is warm. I don’t have a check engine light and the car didn’t lose any perfomance, this noise is going on for 8 months now. I change the oil regurlaly.
I took it to dealer because it has 5 years of warranty, they say it’s a “normal” sound but it doesn’t seems normal to me.
I just have a video of the noise, I know it’s not much but I would like to know if someone has a clue of what’s going on.
YouTube link:
Take off the serpentine belt. Run the engine for just a few seconds.
Does it still make the noise?
If not then the sound is coming from one of the pulley driven accessories.
Turn each pulley by hand to see if they turn smoothly.
Plan B:
Get or make (from a piece of hose) a stethoscope; use to pinpoint the sound.
Does this noise occur only when driving down the road, transmission in gear, at 1500 rpm, or even in neutral in the driveway?
Thank you for answering, I’ll try to do that tomorrow 
thanks for helping.
I think it’s actually coming from inside the engine 
Thank you for answering!
It happens in neutral too
It happens when I’m driving too.
I never heard anything like that
This engine has complicated variable valve timing, suspect you may be having a problem with that. You might try changing the engine oil and filter, if it makes a difference suspect something amiss in the variable valve timing function. VVT engines are very sensitive to engine oil quantity, quality, and cleanliness.