1999 Saab 9-5 Throttle Body failure

I have a 1999 9-5 2.3 4-cylinder that came up with a check engine light at 100K. I pulled the codes with an OBD II which it came up with three separate. I stopped by the dealership and asked them what the codes mean, and the mechanic said it was a throttle body failure. I found a refurbed unit for under $200, and replaced the unit. It ran great for two days, and then came up with the codes again. I pulled the codes again, and they were the same. Is there something outside of the TBI unit that would cause these codes to set? I reset the limp home mode and cleared the codes, but think they will come up again. Is there anyway to check the throttle position sensor on these TBI's?