Went to auto zone they said there are not codes and it ran perfectly today.

ok, well check a few things....

seaford and i worked awhile on trying to fugure out his truck. he had a fault with the ipr circuit. i had never seen that before then, a few weeks later i had one come in with the same deal. the ipr is a 2 wire connector and it is hooked into the high pressure pump. the connector is retained by a gm style clip wire (you have to release the retainer wire to release the connector) it sould be facing up at you.

also, the next time the fault occours. disconnect the icp sensor. it is a 3 wire sensor located on the lh (drivers side) head at the top hooked to the log in the head. you cant miss it. it will make the truck run off of stored values and if it runs ok after you disconnect it is mosty likely the sensor. if there is oil in the sensor cavity then it is bad and both the connector and pigtail will need to be serviced. to aid in parts lookup. the ford base part number of the icp is 9f838 and the base for the pigtail is 12224.

Still would give the EBP tube and sensor a looking at, cheap and easy. But along with the other guy's, (and my previous post) it could be a ICP issue to.

the ep is really only there to ck the operation of the ebp valve. unless it is shorted and making the refrence voltage screw up i would not suspect it. I see many trucks come in with biased EP sensors and no drivability issues. because when it screws up over the baro it ignores it.

heres the pc/ed on it.

Signal Functions

Note: The exhaust back pressure (EBP) sensor is not used on the F-Series 650/750

The exhaust back pressure (EBP) sensor is a variable capacitance sensor that, when supplied with a 5-volt reference signal from the powertrain control module (PCM), produces a linear analog voltage signal that indicates pressure.

The EBP sensor's primary function is to measure exhaust back pressure so that the PCM can control the exhaust back pressure regulator (EPR) when needed.

Detection/Management
An EBP signal that is detected out of range (high or low) by the PCM will cause the engine to ignore the EBP signal and disable exhaust back pressure operation.





Note
After removing connectors always check for damaged pins, corrosion, loose terminals, etc.

DTC Descriptions
P0470 = EBP sensor circuit malfunction
P0471 = EBP sensor circuit performance
P0472 = EBP sensor circuit low input
P0473 = EBP sensor circuit high input
P0478 = EBP excessive during normal driving





kPa EBP (Volts)
0 0
55.16 0.25
137.9 1.45
344.75 4.45
365.44 4.75
413.7 5.00



In Hg PSI
0 0
16.38 8
40.94 20
102.36 50
108.50 53
122.83 60

Don't Remind ME - HAHA.

I always read on TDG and TheDieselStop that the Autozone scanners (actron, etc...) can't read the PSD's worth ****. My Actron won't read anything on my PSD, but my Snap On will....

As far as the EBP sensor's A lot of guys run around with them disconnected....

To expand on what problem I had it was the IPR Wiring Harness (the end that actually attaches to the IPR) and one of the wires had backed out of the harness to the point it was causing driveablilty problems - BUT it always idled fine.

and seaford was so happy to get it fixed that he said we could swap boats for a month or so!:evilb::drink::drink::drink:

even though he figured it out!

[QUOTE=Fixxxer22;3288132]the ep is really only there to ck the operation of the ebp valve. unless it is shorted and making the refrence voltage screw up i would not suspect it. I see many trucks come in with biased EP sensors and no drivability issues. because when it screws up over the baro it ignores it.

Agree, with part of your statement, but the EBP
Exhaust BackPressure sensor
Feedback input; PCM uses this to monitor and control EPR operation; 5.0 volts in, 0.8-1.0
volts/14.7 psi KOEO or at idle, increases with engine RPM/load, decreases as altitude
increases. PID: EBP (pressure), EBP V (volts)

EPR: Exhaust backPressure Regulator, also EBP regulator

Output; For quicker engine warm-up at cold temperatures. If the IAT is below 37°F (50°F
some models) and the EOT is below 140°F (168° some models) the PCM sends a duty cycle
signal to a solenoid which controls oil flow from the turbo pedestal. This causes a servo to
close a valve at the turbo exhaust outlet. The PCM monitors the EBP input to determine if the
EPR needs to be disabled to provide power for increased load, then reapplys the EPR as load
demand decreases until EOT or IAT rises. PID: EPR (duty cycle), EBP (pressure)

Along with oil temp sensor (EOT) all come into play for the idle stratege that the Ecm uses in hot and cold "idle mode". So it does play a roll and will and can show its head in a erratic idle. Have not forgot everthing I wrote while in the design cell, on the Powerstroke design team in the late 1980's. I am sure you are more currant than I, since I do not tinker with the small CI engines that much anymore. Pete

dude! we gotta chat about of some of this stuff. that is so cool that you took part in the design of these engines!

Anytime 503 910-4735, 6.9 and 7.3 only. Bailed b-4 6.0 development, So blame that one on me.. Not trying to ride you, you have given alot of awesome advise to members. Pete

well, i have a old 1990 e series mini bus with a 7.3 idi and she is great. and i didnt think u were riding me. those books are what i learn by. they cant always be right ya know. you learn something new every day.

and the 6.0 is awesome! just got to tweak her a little and she is good to go! and thanks for the kind words.:drink: