Throttle body was discontinued as a new part. Used ones can be found in junkyards and eBay to test with a different unit.
https://www.ebay.com/p/2003-Mitsubishi-Montero-3-8-V6-Throttle-Body-MN137646/1825020686
30+ codes seems strange, and if it runs without the MAF, then it has to be fairly simple. I expect most of the codes are due to running with the MAF unplugged from earlier. I would get a list of the codes yourself. I taught my dad how to use this code reader so he can self diagnose and clear trivial ones(outside air is colder than expected) on his old trucks.
Buy this
ELM327 reader from eBay in your choice of wifi or bluetooth connection. (FYI this reader works with almost any vehicle made since 1997 due to the global OBD-II standard)
Install the app for your phone or tablet.
Connect to the reader and run the app to get the codes.
Write ALL of them down on paper before clearing them.
Clear the codes with the ignition on, engine off.
Turn the key to OFF and let it sit a few minutes.
Restart the engine (with MAF plugged in)
Re-read the codes and write down the ones that have returned.
Post all the codes that were originally there and ones that returned after clearing.
We should be able to give you the causes for them and figure out exactly which parts are bad.
