There is a simple test to check EGR exhaust.
1. Start engine and run on idle.
2. Remove vacuum hose from egr valve.
3. Attach a peice of vaccum hose on to EGR valve.
4. Suck on it (or use a vacuum pump)to open EGR valve.
5. Engine should idle rough.(EGR valve should be closed
on idle or during acceleration).This will prove you are
getting exhaust gases into engine and that passages are
clear.
6. If you suck on the vacuum hose (or vacuum pump gauge
drops )and you can keep sucking air then EGR valve
diaphragm is caput.
The only sure way to test the EGR tube is to use a
manometer and for that you will need to know the specs
from Ford.i.e. what the pressure should be. Anybody know
what they are.You could stick a wire down it (after
removing the egr valve)and measure how far it goes
down. It looks like a [censored] to remove.
It will be measured in inches of water column. Too
technical for some. Also the diff pressure sensor
voltage could be checked.Again you would need to know
the specs.
7. If you have changed the diff pressure sensor I would
definately suspect a blockage somewhere.
Hope this helps
