The check engine light turns on and off with hard shifts from first to second gears, where are the input and output speed sensors located?

I have the car listed above GLS and it's having shifting issues. If you take off in Drive, it doesn't want to go into second. If you take off in Low very slowly then move to second before it hits 2,000 RPMs, it'll normally go. Then third shifts find but it'll get stuck there and doesn't want to catch fourth. I bought some input and output speed sensors, but I cannot seem to find them. The ones I thought under the air filter and at the rear of the transmission don't match. Check engine light comes on and off with hard shifts from first to second gears. Reckon I just need to know where mine is located and what they look like. Thank you for the help.