What damage can happen if you drive with a bad throttle position sensor?

No its dangerous. the computer has no idea what the throttle (gas pedal) position is. I will give you some tips, they are cheap and on the outside of the throttle body however they have security screws which are almost always destroyed when removing. Your best bet is to get a throttle body with sensor attached from a wrcking yard and swapping out the whole thing OR having dealer do it screw almost always strip out when removing old tps then it gets fun. It cannot be on there loose.