Hi, new to the site, so I don't know if this has been addressed before. This is my second attempt at posting, so if it appears twice, my apologies. I am getting a code of 401... Insufficient EGR Flow... I've replaced the EGR Valve, the vaccum regulator, and the DPFE sensor. I've cleaned all the hoses, tubes, and checked the vaccum lines. The coed will occasionaly reset itself then start again. (The check engine light is more on than off). Always code 401. I'm at a loss. Any ideas? It's a '97 4X4 4.6L

Thanks

 

It could be a connector and/or wiring problem between the DPFE sensor and the PCM. There should be 3 wires, +5V, a signal wire, and GROUND.

Rockledge has a great explanation for the EGR/DPFE system on the 3.0L Forum....

 

Thanks for the info, I'll check it out. I found a Ford mechanic, who told me (free of charge) that it may be carbon build up in the throttle body. I'll eventually nail this down. Anyone know how a block heater mounts to the block? Is there a bracket that connects inside the freeze plug hole? What is it made out of? Are there any good pictures out there?

 

Thanks, I'll check into it

 

Same problem I had. Ford wanted $900 and change because the the computer they hooked to said it was the DPSE sensor.It cost a $115.00 at Ford and 2 mintues to put it on. The diagnostic computer charge was $75.00. They say they take the whole throttle body apart and clean it. I bought the DSPE sensor, changed it myself to save the labor $65.00/hr min 2 hours. There was also a $25.00 shop fee on there. Well it wasn't the DSPE. There are 2 ports in the throttle body that get clogged with carbon. Buy a can of Throttle body cleaner,a coat hanger or pipe cleaners and about 2 hours of your time to clean and put everything back together. Then ride to the closest AUTOZONE and have them reset the codes. I have put some 30K on my truck since then and no problem. A mechanic did mine in his front yard in 45 mintues for $100.

 

Thanks... That's exactly what it was. I almost got charged $90.00 for a diagnostic fee, but the mechanic told me in time to avoid it. Sold me a gasket and I cleaned it myself. Those ports were clogged bad. Any advice on how to keep the carbon buildup down?

 

Take the air intake off every 5K or so and hold the butterfly open and put the long nozzle on the can of Throttle body cleaner and squirt it in there. People might disagree with this part(it soften the hoses)but I disconnnect the vacuum hose to the EGR also and squirt some cleaner in there and let it sit over night.

 

Thanks. I'll stay on top of it to keep it from happening again.

 

Go to Autozone before you start next time. They will diagnose
the code for free, then you post if here or look it up in the list of codes on this site.
You can reset the codes yourself by disconnecting the negative battery terminal
for 15 minutes. Your computer needs to relearn everything anyway since it will undoubtably run much better. I had to clean the egr ports and passage, replaced the egr valve, the Idle Air Control Valve, and cleaned the MAS. Runs like a new truck.
The egr port carbon build up will happen to everyone eventually. I did mine at 128,000, so the build up isn't something that happens fast. The mechanics on this site never recommend squirting cleaner directly into your throttle body system, as the body is coated with an agent to prevent build up. The egr port is not coated this way,
so it builds up there. They also recommend not squirting cleaner into an egr valve that you want to keep, as it can damage the diaphram. I used a coat hanger, and some cleaner in the ports and passage, but tried not to get it anywhere else.
Scrape, scrape, scrape, skinned knuckle, scrape.... It was burning oil, white smoke, low mpg, idling up and down. All better now. Just my two cents, worth just that.
This site has saved me major dough.

 

Thanks buddy I was passing on what the mechanic told me to do. I quess not all mechanics are create equal. Thanks again.

 

Anything to try and help a fellow ford truck man. I spent more time in my
engine compartment than I wanted to for about two weeks.
I also had to replace my alternator during that period, as it died.
How many miles on your ride? One code said lean bank #1, but
it was the IAC. So even codes can be wrong, and must be cross-referenced
with symptoms to the homies here.

 

Just filled up and wrote the mileage down on the reciept 152161 and getting a little over 16 mpg other than this p0401 code and having to clean the ports never a minutes problem. Truck ran fine with the ports clogged the check engine lite bothered me. I am ****. My wife fixed it to get it off my mind she stuck a wallet size photo of her there so I would have to look at her everytime I would look at the the lite. That made me want to get it fixed even more.

 

Ha! I hope it gives you no other problems. I bought mine with 126,000 on it and can't vouch for the previous maintenance, but I can vouch for the list
of codes it came with. Of course, the light didn't come on until I had purchased it. You have the 4.6 ot 5.4? Glad it's running good.

 

4.6L. I also have another post the title is "engine stalls after setting it the sun" would read that and see what you think on that one.

 

I'll track it down. Hopefully, RacerGuy or LXMan1 or another guru
will answer it, as I am just feeling my way through the darkness
with their help.