as stated before my 2015 Kia Optima EX with now 121k miles has been trouble, no check engine lights or anything or that nature. I have noticed that when temperatures reach under 30 degrees, it idles really high (2500 rpm) and sounds as if someone’s holding down the accelerator pedal and sounds like a motorcycle if I’m being honest. I’m used to a loud cold start, but it has been making this noise more often now that it’s cold and it’s aging mileage wise. It only does every now and then like for instance, it’s almost the same temperature every morning but sometimes it’s not that loud and other mornings it’s excessively loud even though the temperatures are the same. The noise only lasts for about 10 seconds. Is this normal?? It’s also worth a while to mention how Kia/Hyundai’s GDI system is the loudest I heard compared to other manufacturers GDI’s even on hot days, you can hear the ticking noise from a distance. By far, my car is the loudest cold start I’ve heard out of any, haha... my assumption is that it’s trying to warm up really fast by running excessively rich which isn’t good for the catalytic converter.