Does the OD light start blinking when you're passing, or going up a hill? (heavy engine load conditions) Have you noticed any slipping or is everything operating normally?
There was a post in here yesterday that identified some problems with the newer style (white plastic) TSS in older CD4E transmissions. The weaker signal given off by the new TSS is not picked up very well by the computer in the older cars & will throw a few tranny codes. Solution: Install an old style (TSS) sensor.
HTH
