Joe,
I went to check my books for a "92" series height gage and only found "192". Is your a dual beam and is it digital or dial?
If it is a dual beam style, check one more thing. Put an indicator on the end and run it up and down against something you know is square to the plate. (I know you aren't supposed to use these to check square, but the info is needed to answer the question).
The dual beams use a rotary encoder type thing with 2 gears that ride inside the front beam against the finer rack. The bottom gear translates the vertical movement into rotary motion while the top gear kind of takes up the slack with a coil spring. If your height gage got dropped or violently set down or just handled incorrectly by squeezing the paralell bars together while carrying it around, the perp to the base may be off enough that the top gear is not fully engaging the rack on the upward movement. I have seen this more than once here at work. We have >60 Mit height gages in the plant.
Of course if your 92 series isn't dual beam, forget it. I wish I could locate my CD ROM with the parts breakdown but apparently day shift cleaned up and hid it from me. -Mike