DPFE sensor - anyone heard of this IN

an Isuzu engine?

Dreaded CEL is back on, but the truck is actually smoother then when the CEL is off - this is getting extremely irritating.

Same code P0401, I'm sure everyone knows by now that I've replaced the EGR valve, cleaned those pipes a million times, cleaned the TB, reset the computer so much that the bolt on the negative battery needed replaced last time.

Per Tynan's Isuzu in Denver, the Isuzu engine does not have a DPFE sensor, but I've heard rumors that this 3.2L *may* in fact have one. And also, if it does have one, where can I find it, dealership, Napa, and autopartswarehouse (internet) doesn't carry one for Isuzu engines.

Also does anyone know what else could be linked to the EGR insufficient flow reading? Any other sensors, i.e idle air control, temp sensor, etc.

I know the MAP sensor *could* be related, but I've also heard that it would throw it's own code.

FWIW - all wiring connections are reading fine.

I think DPFE sensor require vacuum line to go to EGR but '97 EGR all electrical.
There is 15A fuse for ECM in engine bay fuse box(look on top of the box it say ECM), by removing this fuse it will reset the CEL also. But the code(P0401) is still be stored in ECM memory and you need 40 cold starts with no failure to remove it from memory. So if say you do 3 starts a day you need about 2 weeks without code and you can pass inspection.
And now VERY wild guess... May be problem is in your ECM. Not sure what you can do unless you have second good ECM and you can swap them to check it out.

an Isuzu engine?

Dreaded CEL is back on, but the truck is actually smoother then when the CEL is off - this is getting extremely irritating.

Same code P0401, I'm sure everyone knows by now that I've replaced the EGR valve, cleaned those pipes a million times, cleaned the TB, reset the computer so much that the bolt on the negative battery needed replaced last time.

Per Tynan's Isuzu in Denver, the Isuzu engine does not have a DPFE sensor, but I've heard rumors that this 3.2L *may* in fact have one. And also, if it does have one, where can I find it, dealership, Napa, and autopartswarehouse (internet) doesn't carry one for Isuzu engines.

Also does anyone know what else could be linked to the EGR insufficient flow reading? Any other sensors, i.e idle air control, temp sensor, etc.

I know the MAP sensor *could* be related, but I've also heard that it would throw it's own code.

FWIW - all wiring connections are reading fine.

A DPFE sensor is a exhaust back presser sensor.
Unless your engine has one ???
The map sensor tells the pcm when to open EGR valve
Ford used them and had a lot of problems with them.
They are usually connected to the EGR valve exhaust tube or pipe with small hoses.
Post your year and model and engine and I will check for info on it.
Your code indicates not enough egr valve flow.
Also check for egr valve passage stoped up.

...
... I've heard rumors that this 3.2L *may* in fact have one. And also, if it does have one, where can I find it, dealership, Napa, and autopartswarehouse (internet) doesn't carry one for Isuzu engines.

what exactly would it take for you to believe that it does not have one? i know -- let's start a rumor that it doesn't have one.
really Ramblin Fever, you spin your wheels way too much when the answer's there in front of you. you don't have one. move on and figure out what's really wrong. :2cents:

Dreaded CEL is back on, but the truck is actually smoother then when the CEL is off - this is getting extremely irritating.
my guess is that when the CEL is thrown, the computer is putting itself in the closed loop mode and that's why it seems to be running better, although the problem hasn't been fixed. {{actually it might be putting itself in the open loop mode, i never get these loop terms straight :rolleyes: }}

iirc, there's a whole diagnostic tree in the helms factory manual about troubleshooting this kind of thing.


hth

the above is rumored to be from
//bc

an Isuzu engine?

Dreaded CEL is back on, but the truck is actually smoother then when the CEL is off - this is getting extremely irritating.

Same code P0401, I'm sure everyone knows by now that I've replaced the EGR valve, cleaned those pipes a million times, cleaned the TB, reset the computer so much that the bolt on the negative battery needed replaced last time.

Per Tynan's Isuzu in Denver, the Isuzu engine does not have a DPFE sensor, but I've heard rumors that this 3.2L *may* in fact have one. And also, if it does have one, where can I find it, dealership, Napa, and autopartswarehouse (internet) doesn't carry one for Isuzu engines.

Also does anyone know what else could be linked to the EGR insufficient flow reading? Any other sensors, i.e idle air control, temp sensor, etc.

I know the MAP sensor *could* be related, but I've also heard that it would throw it's own code.

FWIW - all wiring connections are reading fine.


Well you are lucky it looks like it only has a MAP sensor and no DPFE like a Ford. :lol: :grinyes: :grinno: :lol:

Here is a PDF that tells you how to.
http://members.troublecodes.net/crunch/401isui.pdf
Let us know how it goes.
MT

Rambin, I'm getting mixed up now since you have several threads going on for the same EGR issue.. IIRC, you said you had a strong vacuum from the EGR valve base with the vlv removed and the truck idling, correct? I dont recal you going into detail on any exhaust flow pulsing out of the exh port on the EGR base (at idle). You need to feel/hear a pretty decent amount of exhaust popping out of there. It should sound like an exhaust leak with the valve off and the truck idling. You can stop up the flow easily with your finger/rag, but it needs to flow freely for the system to work.

Joel

Trooperbc - this is the 1st time someone from THIS board has in fact said it didn't have a DPFE, but, some FROM this board have also said that it may have one - I was in fact asking.

Spinning my wheels, what is that supposed to mean and If YOU in fact know the answer, as you said it's right front of me, then what is it that's causing this P0401 code?

Move on to WHAT's really causing the problem, you stated, my answer is WHERE have you been - if you haven't read it before, I have done just about everything there is to do for a stupid P0401 code, THIS is why I'm asking if any other sensors are related that I may have missed.

MT-2500 thank you VERY kindly for your input; I will look more into the MAP sensor area and double check all the wiring.

Rodeo02 sorry for all the confusion, I only started another thread cause I simply wanted to know FOR SURE if anyone in fact knew it had a DPFE sensor. Both EGR holes, little and big, are good and clear at idle - little one has good suction, big one has exhaust coming out and yes, it sounds like a major exhaust leak with the valve off.

We will double check all wiring going to the MAP sensor tomorrow, after this, when we're off at X-mas, I'll have the mechanic fumble with it - probably some stupid $20 part.

Trooperbc - this is the 1st time someone from THIS board has in fact said it didn't have a DPFE, but, some FROM this board have also said that it may have one - I was in fact asking.

Spinning my wheels, what is that supposed to mean and If YOU in fact know the answer, as you said it's right front of me, then what is it that's causing this P0401 code?

Move on to WHAT's really causing the problem, you stated, my answer is WHERE have you been - if you haven't read it before, I have done just about everything there is to do for a stupid P0401 code, THIS is why I'm asking if any other sensors are related that I may have missed.

MT-2500 thank you VERY kindly for your input; I will look more into the MAP sensor area and double check all the wiring.

Rodeo02 sorry for all the confusion, I only started another thread cause I simply wanted to know FOR SURE if anyone in fact knew it had a DPFE sensor. Both EGR holes, little and big, are good and clear at idle - little one has good suction, big one has exhaust coming out and yes, it sounds like a major exhaust leak with the valve off.

We will double check all wiring going to the MAP sensor tomorrow, after this, when we're off at X-mas, I'll have the mechanic fumble with it - probably some stupid $20 part.

You are welcome.
Print off the pfd I posted and go threw it when time permits.
And remember the old map sensors need good vacume and engine running good to work right.
Good Luck and let us know how it goes.
MT

Problem resolved - thank you all very greatly!!

Trooperbc - this is the 1st time someone from THIS board has in fact said it didn't have a DPFE, but, some FROM this board have also said that it may have one - I was in fact asking.

Spinning my wheels, what is that supposed to mean and If YOU in fact know the answer, as you said it's right front of me, then what is it that's causing this P0401 code?

Move on to WHAT's really causing the problem, you stated, my answer is WHERE have you been - if you haven't read it before, I have done just about everything there is to do for a stupid P0401 code, THIS is why I'm asking if any other sensors are related that I may have missed.

ok Ramblin, maybe i was a little harsh. all my comments were directed at the DPFE and lack thereof. you wrote that 3 or 4 places, including the dealer, told you that no, your truck doesn't have one. my "spinning wheels" comment refers to you not accepting their answer, as does "right in front of you".

as to where i've been -- i really don't spend a lot of time trying to piece various threads together, but i did have a very real, though vague, sense that i've heard all this rumor stuff before -- hence my frustration. and i offered my one contribution. . .

glad you resolved the problem :) -- how, exactly, anyway?


//bc

Problem resolved - thank you all very greatly!!

Ramblin, you gotta be kidding. Enough bandwidth used up on this topic to computerize a third world country and you sum it up with "Problem resolved"!!!! C'mon man! Spill the beans!:grinyes: (funnin' ya man!)

Joel

Problem resolved - thank you all very greatly!!

You are welcome and glad you got it fixed and thanks for posting back the fixed.
But would you give us a hint on what the fix was?
It may help somebody else with the same problem.:grinyes:
MT

C'mon man! Are you going to charge for the fix?!?! PM available after PayPal payment!!!?

Ahh, but it's SOO very fun keepin you all in suspence.

Seriously, I meant to reply further on the resolution at the time, but we had a very very mean intruder that suddenly became obvious in our basement that was MUCH more important then a reply.

One of our little dogs got himself cornered by a baby rattlesnake - took a bit to figure out how to get a hold of both without either making contact.

Rattlesnake in the wintertime - man, we got bigger problems then I thought!!

The fix on the truck involved 2 sensors that obviously do not always give out their own codes - the map sensor was definitely a gonner, along with the idle air control sensor.

Tried cleaning the idle sensor, it was just too gummed up. Can't complain, two sensors together weren't too bad considering they'd never been replaced or cleaned before.

Sorry for the separate threads in all this, it's just I wanted to make it obvious that the P0401 code isn't always resolved JUST by cleaning or replacing the EGR valve. Nor is it a simple fix that everyone has answers to.

Ahh, but it's SOO very fun keepin you all in suspence.

Seriously, I meant to reply further on the resolution at the time, but we had a very very mean intruder that suddenly became obvious in our basement that was MUCH more important then a reply.

One of our little dogs got himself cornered by a baby rattlesnake - took a bit to figure out how to get a hold of both without either making contact.

Rattlesnake in the wintertime - man, we got bigger problems then I thought!!

The fix on the truck involved 2 sensors that obviously do not always give out their own codes - the map sensor was definitely a gonner, along with the idle air control sensor.

Tried cleaning the idle sensor, it was just too gummed up. Can't complain, two sensors together weren't too bad considering they'd never been replaced or cleaned before.

Sorry for the separate threads in all this, it's just I wanted to make it obvious that the P0401 code isn't always resolved JUST by cleaning or replacing the EGR valve. Nor is it a simple fix that everyone has answers to.

Glad all is well.
Little dog and truck.
And we hope you took care of the rattle snake to.
But keep a eye out for them more baby rattlers for sure.
And watch out for mama and papa rattler.
I was raised with copper heads coming into the house.
Which are a lot sneaker than a rattle snake.:grinno:
A old rattler will usually stay more out in the open and give you a warning before biting but a old coper head will hide under stuff and just just go ahead and bite if you get to close to him.
So I know the feeling.
Thanks for posting back fix.
MT

Copperhead?! :banghead: :banghead:

Good golly, I'd definitely move out!

Babies are exactly what we're worried about - Mom's don't have just 1 baby. There's more, plenty more - somewhere. Just don't know where, yet.

Scary thing is, babies have more venom then Mom & Pop; I have 3 little dogs, 2 kids that roam the whole house. So far, we've only found 'em in the basement - no this isn't our first, we found 3 others earlier in the summer. But, they had to have been from a different litter, those ones were bigger.

For now, we went through the basement and moved EVERYTHING away from the walls, corners, etc. and we're gonna have to call in a company that does whatever. An expensive situation here in Colorado, because it's not something that Coloradan's normally have to call for - but I am NOT going to live them in my house :shakehead

Outside in our yard is bad enough!

FORGOT to add - on the MAP sensor, it should've been obvious to us when we looked at it 2 weeks ago, as it was broke literally in half.

You must have gotten the parts locally? $$?

The map sensor we'd called on a week ago, Napa had 4 in stock, just didn't bother to get it til the other day - $44

The idle air sensor we pulled off a '96 Rodeo sitting in a junk-yard cross town along with some other parts - charged us $5 for the sensor. Truck was in a roll-over with only 76k miles on the clock.

TrooperBC - Apology accepted; we've all come on strong at one time or another. My reply was pretty powerful just the same.

Thanks for the info!