You will see a lot of information out there that says throttle position sensors cannot be rebuilt. Maybe so, but they can be dismantled and inspected.

This is tricky work sometimes, sometimes not. Just removed the TPS, find the small tabs on the sides that hold the cover on and remove the cover. Easy, don't break the tabs.

The inside might be clean and bright or they might be frosted over. This can be cleaned and checked with the ohm meter. But many times you will find burned marks on the copper runs. These scorch marks can be filed off (sometimes) and the TPS make like almost new.

But if the burn marks are too deep or the the copper tracks are warped then you will just have to search for a good used one.

Sometimes these burned spots can be papered over with the same type of repairs you might make on a printed board, but this is precision work and should only be preformed if a replacement cannot be found. This is because this repair usually will not work that well if at all.