I have a 2004 F250 with a 6.0L TD that I bought used about 3 years ago. It currently has about 97,000 miles. It's bone stock and we use it to pull a fifth wheel travel trailer. The previous owner had the turbo replaced and some other minor repairs.
I have had the EGR valve replaced and most recently had a bad injector replaced.
A couple of days ago I had a check engine light pop on. I checked the computer with my Actron Autoscanner plus, and it shows three codes:
PO4070 Exhaust pressure A circuit
P2262 Turbo/Supercharger boost pressure not detected mechanical
PO4070 Mod $00 Exhaust Pressure sensor A circuit pending.

Is this pressure sensor something I can replace, or is it some other issue. The engine seems to run fine. About 3 weeks ago, the pipe on the back of my catylitic converter came loose and I had it re-welded back. No other problems until now.
The muffler shop owner said he could remove my converter and factory muffler and replace them with a performance muffler which he said would "help it breathe". I live in a rural area that does not require emissions testing.

From everything I have read on this forum, the 6.0 is susceptible to heating issues. I do not let the truck idle very long.
Any help would be appreciated.

Thank you,