Hello! I just got this little pickup yesterday with 166km on the ODO, VIN: JT4RN81R0K5003619
It has a 22R as indicated when I look under the hood and see '22R' and a carburetor...
But I am confused as when I enter this VIN on www.oreillyauto.com and the vehicle info shows the engine as a 22RE
However on other VIN decoder websites its not so clear cut and showing a 22RE. I even had some that shows three motor options

How do I find out what motor this VIN had when it left the factory?

 

https://www.toyodiy.com/ is a helpful resource for accurately finding part numbers and helping you figure out some vehicle specifications.

Their information is from Toyota when your truck was new.

I entered your VIN into their Vehicle Identification section and your truck shows up as having the 22R carbureted engine, which is what you still have. https://www.toyodiy.com/parts/q?vin=JT4RN81R0K5003619

This looks like a base model for a 1989 2WD Truck, which commonly had the 22R.