Hi I have an 1989 MR2 mk1 AW11 and I have developed a system that allows me to talk with the ECU processor.
This allows me digital access to all current engine management data. If the ECU is similar for the Corolla I could do the same for your cars. I can even monitor to see if there are any diagnostic error codes stored in the processor RAM.
I can also datalog this data and display a histogram of the data. Interested? See an image on
http://www.jmross.freeserve.co.uk/page1.html
email me if you want to know more.