okay so i have further insight to what is exactly going wrong with my car. Every time i crank the car and take off it goes great through every gear until 3rd. Once its in 3rd gear it stays in that gear the entire time and will not shift to 4th. unless you turn the car off or manually shift down but you only have 1st,2nd, and 3rd.. But the weird thing is, i can be driving and then BAM! the check engine light will disappear and the car fixes itself and then it shifts perfect as if it has never had any problems at all. its so random. but here lately the majority of the time its usually stuck in 3rd. anyone have an idea please. thank you so so much. sorry if this is considered a repost. could it be a shift sensor possibly or maybe even a ecm or wiring problem? thanks alot everyone.