DPFE sensor....WTF is it?

[cozz]

2.3 duracrap, inherited the truck, stutters at low to mid RPM's....have replaced coil pack (had a crack in it) wires, and plugs....got frustrated and thew a part at it...TPsensor. truck idles great, and throwing no codes....don't want to take it to Ford....I'm thinking it's on the back of the head, near the firewall, am I right?

 

[RonD]

EGR Valve is at the back of the intake


DPFE = deferential pressure feedback

It measures the pressure difference in two hose connected to it, and sends the info to the computer on the wires connected to it.
So DPFE sensor has two hoses and wires

The DPFE hoses are connected to the exhaust system, one close to the EGR valve and one farther away, often both are on EGR Valve's metal tube to exhaust manifold.
When EGR Valve is closed the pressure at both hoses will be the same, no difference.
When computer opens the EGR valve the hose closest to the EGR valve will lose more pressure than the other one, so there will be a difference, the computer can tell how far open the EGR valve is by how much of a difference there is in pressure between the two hoses.

 

[pjtoledo]

fyi, Duratecs can last damn near forever. my '05 has 308,000 miles on it.

 

[cozz]

my research suggests

that the pressure feedback sensor might be going squirlly or the egr is acting up...I just want to get to the components, and figure out how to test them....I have heard rumors that the feedback sensors can act funny, and not throw a code...
so it's off with the intake again? lol, just put it back on after replacing those heater bypass hoses, and the pcv valve

really like the truck so far, and it's only got 70000 on it, runs great otherwise...but I hate that plastic s*****y intake manifold
thanks for the info

 

[cozz]

well, the intake runner junk is the problem

I finally said f*** it, and took it to the dealer....they said their little laptop had a stored code of p1512, and they wanted to replace the intake to the tune of a grand, but once I now have a code, I will not be needing their services, lol....
Sooooo...it's either the runner control solenoid, or the intake. I am figuring I will replace the solenoid first, because it's the cheaper of the 2 choices (altho not really cheap- 150 bucks- ouch) and if it doesn't fix it, replace the manifold. Kills me, the same Dorman parts on Rockauto are 200 bucks total, verses local which are 400...especially for that cheap plastic manifold- junk to me
Even if it fixes the problem with just the solenoid, I'll probably replace the intake, as it just looks like it's made to break, but I'm not paying anymore than I have to, for something so cheaply made... I will keep the old one, and remove the flaps for the next time this gives me trouble....I would just do this now, but I just need the truck running as it is my work truck. I've been researching this for a month or so, and there are a lot of Rangers doing this same thing, and people can't figure it out. I will post a follow up for anyone else being driven crazy by this

 

[RonD]

Almost any auto parts store will read codes for you for free.

You can also get a Bluetooth OBD2 reader, for under $40, it will work on any vehicle sold in the US or Canada after 1995, so good long term tool to have.
You need a smartphone or tablet/laptop with Bluetooth to use as the display for the reader.
Nice thing about these is that besides reading the codes you can also watch Real Time sensor data while engine is running and vehicle is being driven.

p1512 and p1537 seems to not be uncommon on the 2002 2.3l Rangers, the IMRC(Intake Manifold Runner Control) system often got cracked vacuum lines, so check and repair those first, not the solenoid.

Location video here: https://www.youtube.com/watch?v=YgikQ8s6Va0

 

[pjtoledo]

fyi, by the time they made my 2005 the intake runner solenoid had been eliminated.
I do not know if they can be interchanged.
the heater in the T-stat is also gone.

 

[RonD]

fyi, by the time they made my 2005 the intake runner solenoid had been eliminated.
I do not know if they can be interchanged.
the heater in the T-stat is also gone.

The problem with making those changes is the 2002 computer needs to see those systems.
So you will get a CEL(check engine light) if there is no electric thermostat feedback and I assume the same with no IMRC solenoid feedback.

I know some leave old thermostat connected but just hanging there, and use the non-electric model in it's place.

 

[Soledad]

Damn, just saw this.

The IMRC solenoid kicks in at around 2000 RPM. Using a laptop, OBD2-USB serial cable and the free software on forscan.org you can see the Solenoid actuating.

I was having a bucking problem about mid throttle and found that my IMRC actuator arm at the back of the intake right next to the firewall (a real pain to get to) had popped off the ball for the flaps. Once I put it back on things got much better but it's not perfect. Every now and then it pops off though and I have some loud IMRC flap tick at idle and so I've got a new Dorman intake ready to be put on some time in the near future. Oh and yeah, like RonD said the IMRC vacuum hoses will crack.

Yeah, you can pull the long rod out of the flaps, remove the flaps, seal up the holes with epoxy and leave the IMRC solenoid plugged in so it doesn't light off any codes. But some who have done this have noticed a lack of low end power and went back to the flaps (which is what they help with).

I run a 2006 Ford Motorcraft thermostat in place of the electric thermostat. I have the electric one still plugged in though (so it doesn't pop any codes) and tied up out of the way for the moment. Truck runs just the same. I bought a 1500 ohm (25 watt I think) chassis resistor to replace the electric thermostat with (again so it doesn't cause it to set a code) but just been too lazy to solder it in.

I think the only differences between the 2001.5-2003 and 2004+ 2.3L's was that in 2004 they got rid of the IMRC system, got rid of the electric thermostat, had revised intake and exhaust cams, new ECU and I want to say maybe a new exhaust manifold (not to sure on that one though).