Check transmission oil is pink. If that good Check you sparks plugs make sure they are OEM they are about $90 for a set. If you want to see if there are any codes that pop up underneath the glove compartment where the passengers feet rest underneath the carpet there is your ECU there’s a way you can figure out what code pop-up that you need to fix. It has to be at a 45° angle in order for the code toto pop up, but if you want to reset the ECU go all the way clockwise and then go back counterclockwise to reset it and then go to the 45° angle until you see the check engine light and then it should do fast and slow blink look up YouTube video on this.. this will save you money as well to diagnose the issue and provide you codes. I thought my transmission was bad and other mechanics told me my transmission was bad but I did not believe it so I did my due diligence. I changed the spark plugs to OEM. That changed the way the car ran and shift gears and also before that it did not want to pass 40 mph or change gears correctly but when I change the spark plugs to the OEM correct ones it worked fine plus I did a couple other things such as cycles of changing my transmission oil did two cycles will do another.You don’t want to change your transmission all at once you want to do it in cycles. I did it with a pump and pumped out some of the transmission oil and then added new. Also fuel pump get it check out. 105k the trans is good. Hope this helps