P0401 Insufficient EGR Flow.
P0402 EGR Flow Excessive at Idle.
P1405 Differential Pressure Feedback Electronic Sensor circuit Upstream Hose.
First off, how can you have insufficent and excessive? kinda confused. Next, what the hell is 1405, and how do i fix that. I need to get this done asap as I need to get my car on the road again, due to my tabs being expired.
also, how can I reset the check engine light, so I can go take it while its off, so i can pass.
I doubt it will stay off for long.
You may just have a bad DPFE, but check and see if the upstream hose is off. If it is, you probably have clogged preCATs.
Reset the engine light by removing your battery cables for ~10 mins, the putting them back on. You're PCM will re evaluate itself, then come back on once it knows what's going on with the engine. Mine comes back after about 25 miles of driving, other peoples comes on faster, and others takes longer.
But when I took mine to get tested, the CEL was on, and I thougth the car was running rich, but I passed with flying colors.... Did they guys just hook me up, or did I just pass on my own?
The guys failed me, because there systems usually make it come on. And well, it was already on. Then when it failed in those three places, they said you failed for three reasons. So now i gotta get that fixed asap, as my car is parked in my parents garage at their house till further notice.
Originally posted by PlatoSVT:
Reset the engine light by removing your battery cables for ~10 mins
There's an alternative method that takes proly no more than 1.5 min. 
Just pry open the fuse box (engine bay) and pull out the fuses # 4 and # 11, wait one minute and put them fuses back in. That's how I took my CEL off, which - knock knock on the woood - never came back.
lol, I will have to do that, much easier then waiting ten min. Will it reset my stereo settings, (i don't think it will, but i still hate when it does lol)
Originally posted by auiotour:
P1405 Differential Pressure Feedback Electronic Sensor circuit Upstream Hose.
I still would like to know what this means if anyone could possibly tell me if they know even.
When was the last time you did
this? Start there. Check to see if your vac hoses have come off the DPFE sensor, if there was excessive backpressure that blew them off, that would explain the excessive/insufficient contradictory codes - or your EGR valve diaphram blew. If the hoses are off, you may have clogged precats.
Originally posted by auiotour:
Will it reset my stereo settings, (i don't think it will, but i still hate when it does lol)
I don't think so; the microproccessor chip in your stereo stores the info regardless of the powering status. Again, I am not sure LOL but it makes sense. Wait, I meant the fuses disconnection, not the battery terminals; however LOL I don't get why even disconnecting the battery would interfere with your settings. If you disconnect your comp from a power source it wouldn't change its time setting, now would it?
my stereo forgets all, no memory, unless the memory power cord is hooked up.
I have never done that, but I will have to. I am still gonna try to reset the PCM so I can get my car back on the road, but then, clean it tonight. How long does it take, anyone know?
So i checked out your link TourDeForce, and went home, and attempted it, very simple to do. Still gotta little cleaning to do, and putting it back together. I just bought the gasket, and will be installing it within a hour or so. Excited to get my car back on the road. Also, the EGR Sensor, where is it as I might need to replace mine, and Well, the junk yard is the place to start for me. I don't mind paying $5.00 for a used one, if that even, the yard I go to is very reasonable about giving small things for a couple dollars if not free. Thats where I go to get my head light and fog light bulbs. lol.
BTW, all of those three holes, plus the one on the throttle body were completely clogged.
Auio,
The DPFE (Differential Pressure Feedback Electronic Sensor) is like under the TB bolted to the side of the engine. It has 2 hoses on the bettom of it to sense pressure (obviously) and an electric connector on the front surface.
They commonly go bad on our cars, i bet that is the problem. So far i've replaced one on my sis' 99 3.0 Duratec taurus, and my old 99 2.5 duratec stique. The old ones had a case made of metal and they were manuf. by kavlico i believe; the new one (which you want) has a case made of black plastic and its made by Motorolla. I say just buy one new, you don't want the old poorly designed ones which prematurely fail from a JY.
Its easy to change, just scrape the old hoses off of the metal one because they're most likely melted on, then just swap.
The accordian tube and some other crap needs to be moved to gain access to the area.
Fwiw, i believe that ford used only one (or a small # of) DPFE sensors for the last few years, so if you get lucky, look for a black plastic one from the JY.
I will look in a few minutes, but I am still not sure where I am looking at lol.
Okay, i found it, but first, let me start with this:
I cleaned my Throttle body and the UIM. Wow what an amazing difference, after I cleaned it. Then my dad cleaned it even more, he found [censored] lurking in dark holes, and well got twice what I did, and it was already sparkling when I cleaned it. I bought a new gasket for 2.99 from napa. Returned to my house to put everything back together, reset the pcm, and drove for almost 2 hours. Nothing. So, I figured I would drive my car home, and then to the emissions station in the morning before I went up towards canada with my sis tomorrow. As I am driving, i miss the gear the the rpms sky rocket to about 6k. POW I see the Check Engine Light come on. How sucky is that. So tomorrow morning, I am going to go buy a new piece at the junk yard to replace that sensor you guys were talking about, hopefully this will solve my problem. Till tomorrow. Thanks everyone for the help.
Its nice to know the Differential Pressure Feedback Electronic (DPFE) Sensor, on the pre98s, had small bolts going through them, and on the post97 models, had larger bolts going through them (from the engine block). I just tried to install one from a 95, only to find out that well, it doesn't fit, time to go buy a drill and drill bits. this sucks!
So, I noticed some other things that are different. The harness for the sensor is different from the pre98, and post97. The post97 is larger and the pre98 is smaller, just like the holes. So I am gonna return it and say well, i couldn't even hook it up due to the different sized holes, and the connector is different. he said if I used it that He would only allow me to exchange. I will see if they have a different one that will fit. Otherwise, I will have to get one from the ford dealer tomorrow. Any clue on the costs.
Fordpartsonline says $70 for them, $85 list. What i was saying earlier is look for DPFE sensors from other late model ford cars, specifically duratec taurus' from the last few years, i know they use the same exact sensors.
Now that you know what it looks like, you should be able to identify the correct one quickly.
Try to get teh plastic one....
I am gonna go look for a new one today. They didn't have any taurus unfornently.
here is what that piece looks like
in this picture I used a dremel and a drill bit to make the holes on the left larger to fit the bolts they needed to go through them. To bad, the plugs are different.
Okay, so I pulled a MAC sensor, or whatever you guys called it off a 98 Mercury Sable. Same Part Number and everything. I install it (along with my new fog light bulb I got for free) and everything is running well, Check Engine Light still on. So I pull the codes at Schucks. I got P0401, and P1405. So I reset the codes using their Code Puller. I leave to go drive for a bit. And within 4-5 minutes it turns back on. So I go back reset it, just incase it didn't do a good job. Start driving it comes back on. So I figure drive to my parents place and pull the fuse. So I do. I let my car idle for a minute or two, and put it into first. BAM it comes back on. I go to Schucks again. This time it pulls a P1401. Which is Exhaust gas re-circulation system (EGR) EVP Sensor Circuit High Voltage Detected.
The print out tells me that the trouble code met qualifications to post, but is no longer present. It appears after off and on. And since the car with the old sensor never had this problem. I am think that maybe this sensor is bad too. So tomorrow. I hunt for another one. This time gonna grab one out of another taurus/sable. But little by little its getting fixed.
Originally posted by auiotour:
As I am driving, i miss the gear the the rpms sky rocket to about 6k. POW I see the Check Engine Light come on.
6k does not qualify as skyrocketing. 
Maybe you should check the exhaust backpressure. If you have high backpressure it will blow off the DPFE hoses and possibly damage the DPFE, giving you a P1405 or P1401. If the engine does not pull like a scalded dog at 6k you have backpressure.
You also need to check the rest of the EGR system. Manually apply vacuum to the EGR valve. If the valve opens and the passages are clear, the engine will almost stall. First time I cleaned mine I missed some crud in the internal passage in the UIM that goes all the way over to the EGR valve.
P0402 EGR Flow Excessive at Idle is usually a sticking EGR valve or a leaky EVR. The EVR is between the coil pack and the IAC.
Well codes P0401. P0402, P1405. Are all fixed. I had just stuck the new sensor on and drove to schucks, whiped the codes, and drove off, within about two minutes it showed up again, so I went back, and it was P1401. But according to the Print out, the problem was seen once but is no longer there. I just installed it, drove maybe 5-6 minutes to schucks. not very far. I don't think it had time to damage it. I think it might have been damaged already.
Problem is now fixed, I checked the wiring harness, and it felt not on all the way, i pushed it in a bit more, then went for a drive, after clearing the codes. Well, NO CEL Light!!! I am so excited. Tried to stop by emissions but they were closed at 1pm. SO I was 20 min late. Got my breaks, gonna install them tomorrow!