Think I found the answer. Bought new high temp hoses for the DPRE sensor because I couldn't find the high side hose. Apparently, someone had replaced the high side hose with plastic gas line tubing that melted and let hot gas spew on the sensor. They had pulled the plastic tubing off before I got there.
If the new line blows, could indicate a serious, costly problem.
On-line search shows that the usual problem is high back pressure caused by a clogged cat or muffler that creates excess heat and pressure in the egr line.
Yeah I have seen exhaust gases leak out and cause that issue.
The flex hoses that are replaced have to be hi temp.
It is very easy to check for restricted exhaust system which includes the cats.
Install vacuum gauge on the engine
Strat up the engine and wait until it is warmed up.
Once warmed on curb idle observe the vacuum gauge
What ever reading it has that reading should remain steady. IF the reading slowly drops to a lower level the exhaust system is restricted and not allowing all the exhaust gases to flow out