Why does car only run in second gear.

First check the transmission fluid level. You will need a special dipstick tool you can order on amazon. https://www.amazon.com/gp/product/B075SVZB4B/ref=abs_brd_tag_dp If that's ok if could be an issue with a part called a conductor plate. Its on top of the valve body so its labor intensive. If you need help from a shop here is a link to find one. https://repairpal.com/repair-shops Alex