Originally posted by tiv:
the 'insufficient egr flow' is usually caused by a sticking
valve. remove it and spray intake cleaner into all 3 openings
liberally.
If you had done it and didn't help, replace it.



EGR valves are much more dependable than they used to be. Check for sticking visually before replacing valve. Passages in the EGR tube, valve, and intake manifold distribution passages are prone to clogging. These will have to be cleaned out to restore EGR gas flow. Virtually every car will eventually suffer clogged passages at some point, a much lesser number will suffer inoperative EGR valves.



Originally posted by tiv:
The rectangular metal box next to it is the
DFPE sensor.



That is the DPFE (differential pressure feedback EGR) sensor.

"Those who cannot remember the past are condemned to repeat it" -George Santayana