Engine Code Po 401

I recently just resolved my issue with the evap emmission sytem, only to come up with another code 2 weeks later. This time I have code po 401 insufficient egr flow. My question to anyone is should I suspect the egr valve itself or could it be linked to the dpfe sensor? Both are original and i know that Ford has had a lot of issues with these dpfe's. 95 ranger 3.0 110k. Thanks in advance for any info on this issue..Joe

From what i have seen once you replace one sensor you will start replacing the rest of them in that system one at a time. Basicly what happens is when you replace the first one the rest of them are so dirty and nasty so your range is all screwed up. you may be able to get by just cleaning the dpfe sensor with some carb cleaner.

From what i have seen once you replace one sensor you will start replacing the rest of them in that system one at a time. Basicly what happens is when you replace the first one the rest of them are so dirty and nasty so your range is all screwed up. you may be able to get by just cleaning the dpfe sensor with some carb cleaner.

Thanks I will try that and if it fails replace the DPFE..Joe

I just fixed a P0401 code my my 96' 3.0 L Ranger. Turned out to be a plugged passage in the intake manifold due to carbon build up. The way I figured out that this was the problem was that when I opened the egr valve at idle using a vacume pump, RPM did not fall off. Of course this is after I spent about a day checking all of the other components. If you remove the black rubber duct from the front of the manifold, and open the butterfly plate, you may see black carbon build up about 6 inches back on the drivers side of the manifold. This is what is restricting the flow.

I fixed it by scrapping away the carbon with a coat hanger from both the front of the intake manifold through the butterfly plate valve, and from the EGR port (EGR removed of course). Took about an hour and much cheaper than trying to replace all of those components one at time. I hope this helps somebody before they waste allot of time.