Arg.. Ford EGR problems...

[SpatiallyAware]

I have a ranger with the 2.5l lima motor w/ 130k or so miles on it.

Last week, ON MY WAY TO THE EMISSIONS STATION it popped a CEL - went to autozone, and it's p0402 'EGR flow excessive'

So - being that it's a Ford I determined that 99.9% of the time it's the DPFE. I replaced it with a new Ford DPFE with no luck. I've removed the EGR and it looks good and the diaphragm seems to hold pressure. The valve opens and closes properly with vacuum. All of the vacuum lines look good, but I don't have a great way of testing them - they are the new style and don't look like the type to dry rot


I'm not really sure where to go from here - trying to research this code EVERYONE states it's the DPFE. There really isn't much in the way of suggestions after that other than removing the intake manifold and cleaning the carbon out of it.



Thoughts? Anyone know how hard it is to remove the intake manifold? I'm working 12+ hour days and I've been fighting this for a week or so.. I'm about to drop it off at the dealer..

 

[Squisher]

You have to take the manifold off?

I got an insufficient EGR flow CEL on my '98 F150 (4.6L) and all I had to take off was the throttle body and the riser. The riser is really a 90 degree elbow so as to mount the throttle body vertically.

If you put a stop watch on me I bet I could do it again in 45 minutes.

btw-my mileage went up by 33% after I did it

 

[SpatiallyAware]

From what I understand my intake manifold has lots of tiny passages through it, and the best (only?) way to clean them is by removing it and poking wire through the passages.


FWIW I seafoamed it and now have a fairly bad misfire. Arg. Time to change out fouled plugs.