1998 Cherokee wont shift out of first gear. it all started when i cleaned the nss and reinstalled it. reverse lights work and it starts right up. Check engine light came on right after i started it to. Dont know what could cause this unless the nss isnt adjusted right. Any help is greatly appreciated...

What's your code

The strategy for a situation where you have a check engine light is always the same. Pull the code.

For a 98, you will need either a code reader, a scan tool, or bring it to a parts store like Autozone that will read the code for free.
Post the EXACT code number here (not a description) here for comment.

You may very well end up readjusting your NSS. Especially if this happened immediately after you cleaned your NSS.