So the old girl has been stalling under deceleration while warm. Pulled codes and got 334r and 172r.

Checked on the o2 sensor and found it to be broken. Amazon sent me one for $30. Installed it and cleared the 172 code but not the stall.

Decided to start digging into the egr system. I popped the vac line off the egr thinking that I would actuate it with a hand pump and check for vacuum leaks. The vac line boot went flying across the engine bay. I guess I will be replacing all these vacuum lines next.