Oven seems to work ok, but heats up way too hot

This is a natural gas Kenmore digital gas range. It's about 10 years old.
The clock / controller board was replaced about 4 years ago, for a different problem.

Everything seems to work ok, no error codes, etc. If I set the oven to bake at 350,
it pre-heats - it stops pre-heating and displays 350. It then cycles on and off. But it's
way too hot, it burns food. I went into the "Oven Temperature Control" (on the
digital control panel) and set it to minus 30 degrees. I have a round dial analog
thermometer in the oven and it measures about 425 degrees.

I removed the oven sensor from the oven and measured it, and it measures 1082 ohms
at room temperature. I put the sensor back in, and disconnected the connector at
the controller board, and measured it there, I got about 1090 ohms ... so I don't
suspect the sensor.

If this ends up being (needing) a new controller board, I'll probably scrap the oven.
I called Sears to fix it last time. The board was $380 - they shipped the board to
my house, and set up an appointment to put it in, and never showed. (and they
wanted $175 to put it in. I ended up putting in the board myself.)

Any opinions? Thanks for your time,

Mike