P0470 exhaust pressure after starting at 0 degrees and 6500 ft in west yellow stone 1500 miles from home. Any thing I can do? Thank curt

 

Likely something with the EBP sensor. If it's running fine you are probably ok to leave it for now.
If it's running badly it might be time to take it off and clean it up good, but more likely the tube that goes to the manifold is caked with junk. It can be cleaned with some weed trimmer wire. Same goes for the sensor, gently tap and clean any junk out of it.

Be sure the wiring and plug is good.

 

Now you know why Ford went to the inferred PCM strategies

Ford always solves hardware problems with software unless it's absolutely necessary to do it with hardware. They didn't want to even try to come up with a revised sensor that was heated or somehow wrapped and with them clogging and not something they or customers were willing to service, it was easier to write it out of the latest programming and use it as a voltage reference.

So the long and short of it is, Don't worry about it

 

I thought this only applied to early builds?

Or is that only P0472?

 

The TSB states it (the inferred EBP strategy) was only for the 03 and early 04 (pre 9-03) model year engines

 

Nope

It INITIALLY was applied to 2003 and 2004 trucks, but it was applied to all builds as the flashes went on.

VXAPXXX for 2003
VXBC9XX for 2004
VXCF9XX for 2005-2007
VXDB1M3 and VXDB1MZ for 2005 Excursions with a 2005 Engine

Curt has a 2004 Engine, so he ended up with a VXBC9 strategy. IF he had VXBC1, VXBC3, VXBC4, VXBC5, his truck would have a hard time starting or wouldn't run right until it warmed up because these strategies relied on the EBPS for reading EBPS. It wasn't inferred through the EGR valve, MAP, and Barometric pressure sensor like it is now.

 

I am going to have to question that!!!

Folks that have the inferred strategy don't get actual EBP readings (not from the PCM anyway). I have not seen any 05's and up that didn't have a functional EBP that the PCM would read (including mine). Now if the EBP is disconnected or is faulty (depending on the fault), it will default to an inferred strategy.

 

I've had two tuners look at strategies for me even The King of PHP himself Bill and he broke it down for me. On some it gives a reading on others it doesn't.

 

Thanks for the quick response! Normally we don't drive for the week. With low snow we trailer 35 miles. I cleared the code before we left and it hasn't come back!,

 

The Ford document below was issued in 2006. At that time it specifically stated that the inferred flash was for 03 and 04.25 (to Sept 2003) model years only.

http://www.flatratetech.com/downloads/diesel_8.pdf

Same w/ the Ford 2009 TSB:

http://www.powerstroke.org/forum/att...bo-relearn.pdf

What am I missing??!!

 

I do have the VXBC9 strategy, and I use Matt's tunes, if that matters.

 

Where is your ICP sensor located?

 

So what you are saying is that the 03 and early 04 did not have the capability to infer the EBP value, so the 06E17 action (in mid 2006) was to install the software to infer the EBP value in these early model years. When doing that Ford completely did away with using the EBP - FOR THESE MODEL YEARS when the software update was applied.

After Sept 2003 (for the late 2004 and later) the strategies had the inferred EBP "capability" programmed in.

I can see that. That makes great sense. That is why we (with the later model years) can run w/ the EBP disconnected.

However, I do not believe that when the EBP is functional and reading appropriately (as well as the PCM can determine anyway), that the inferred value is used. I believe that the actual EBP reading is used when the PCM believes it to be accurate. Clearly the PCM can see the EBP sensor output and translates it to an EBP pressure in these later model years. Also clearly (at least it appears that way to me) is that in the early model years that have had the 06E17 action applied, the PCM does not see an EBP sensor output.

What do you think Razi? Could this be the way it is?

Edit - the presentation states that the EBP is inferred from the MAF, MAP, and VGT command. You stated MAP, EGR, and Baro. I can see where you are coming from on the Baro and EGR, just don't understand why the training presentation is different.

 

How's the snow?

 

Well, this thread sure throws a ton of "knowns" out the window.
All these years we have been told/giving bad info? Is this something new or do more folks realize this to be true?
I wonder why the case of some guys cleaning the EBP sensor and/or tubes and getting good results applies then if all sensors are just inferred? (unless it's a VREF issue)