Good morning.


After reading many threads on here and trying to get my new-to-me excursion to a level of mechanical comfort for me, I came across EBPV sensor and KOEO test. So I did the test and it showed EBPV to be a few (2-3) psi lower than the MAP sensor. Now I am assuming, and yes I know what assuming does, that the MAP is reading correctly since it is around 14 and unless memory serves me incorrectly, that is atmospheric pressure at sea level....give or take a bit (I am also assuming that this is what the MAP sensor reads since it is atmospheric pressure).


So I ordered a new on through Riffraff and installed on truck. Since I already installed a new tube a few months ago, I went ahead and ensured that all fittings and the tube were not blocked or plugged. Completed install and once done with my Redhead group buy steering gear install, I tested again. This time KOEO and EBPV read 0 and MAP 14. UGH What did I do wrong or what should I check next? I was under the impression that doing this KOEO test that EBPV and MAP should be about the same. Seemed like a relatively easy install process and everything hooked back up so not sure where I could have went wrong. Oh and when driving around, EBPV did rise to high of 5-6 according to go pedal position so that tells me that sensor is working.


Oh and before you ask or say anything, I know that my sig line is not yet setup and apologize so here is background. 2000 4wd 7.3l Excursion. 270,000 miles. FRx, HPx, intake plenum inserts, new boots, new radiator, 6.0l 31 row trans cooler, Edge Insight CTs, Redhead steering gear, all fluids changed, 4" exhaust, AIS intake, TS 6 Position chip. Not sure if I have missed anything else but that should cover it for now I believe.


Thanks guys. I really would like to get this fixed b/c getting ready to head down to GA today and would like the better mpg if I can get it

 

Can I possibly be reading the wrong "MAP" reading on the Insight CTs?


When I pick the PID it says "Manifold abs Pressure". I think that is what MAP stands for but want to make sure that I didn't have a brain fart and make a boneheaded mistake.


Thanks.

 

Yes, that's MAP. What does the PID say for exhaust back pressure? Is there one for absolute pressure and one for gauge pressure? If there is, the absolute pressure should be about the same as MAP and gauge should be zero with the engine off.

 

PID for EBPV says exhaust backpressure valve (assuming that my memory serves me correctly). I will check this. That may make a difference. I could swear that I am using the same PIDs that I was before I did this replacement (I was getting about 12 for EBPV and 14 for MAP with old sensor......from what I read they should read about the same or within a few tenths).

 

Is it possible you are reading the wrong PID? For example, I think what you are looking for is the exhaust back pressure sensor (EBPS), not the valve. If I am not mistaken, the EBPV is used to help warm the engine when cold and can also be used as an exhaust brake with some tunes. The EBPS is used in correlation to the MAP in order to keep the truck running well.

If I am wrong in assuming (see what I did there?) then just disregard all of the words above.

 

I could be reading the wrong PID since I am still learning what is what and how to use the Insight CTS monitor. Since it plugs into the OBD port, I am not sure exactly what it is that the PCM/ECM (whatever the correct name is for our trucks). All that I know is the two that I am comparing on my monitor read "exhaust back pressure" and "manifold abs pressure". The EBP is the only thing available on this monitor that monitors/reads anything having to do with EBP and based off of threads read on here on how to compare and diagnose a bad EBP sensor that is what I need.
Honestly I hope that you are correct and it is something as simple as that. Thanks for the input and I will do more research in the am. Time for some shut eye now though.

 

I am not familiar with CTS, but here are the PID's and associated information that I copied from a post by Tugly. Is it possible to verify the PID and the equation on CTS with what is below?

Long name:Barometer
Short name: BARO
PID: 221442
Max/Min: 15.0/10.0
Unit: PSI
Equation: ((A*256)+B)*0.03625
Header: C410F1
The Min/Max values above are for realistic altitudes, but those who traverse the Rockies may see lees than 10 PSI (over 10,000 feet). If you do, you can change the Max/Min to 15.0/9.0.

Manifold Absolute Pressure
Short Name: MAP
PID: 221440
Units: PSI
Max/Min: 45.0/0.0
Equation: ((A*256)+B)*0.03625
It is important that this reads the air pressure of your altitude in PSI (same with EBP and BARO) with Key On Engine Off, then it just adds boost to that while running.

Manifold Gauge Pressure
Short Name: Boost
PID: 221440
Units: PSI
Max/Min: 30.0/0.0 (stock) 40.0/0.0 (performance)
Equation: (((A*256)+B)*0.03625)-[221442]
"-[221442]" subtracts the Barometric sensor (located on the PCM on some trucks, external on others) reading from the MAP reading - and this gives you just the boost pressure above atmospheric pressure.

Exhaust Back Pressure (Absolute)
Short Name: EBP
PID: 221445
Units: PSI
Max/Min: 55.0/0.0
Equation: ((A*256)+B)*0.03625
It is important that this reads the air pressure of your altitude in PSI (same with MAP and BARO) with Key On Engine Off, then it just adds Exhaust Back Pressure to that with engine running. About 53 PSI is sensor limit. Exhaust or boost leaks can make this reading very jumpy during WOT tests.

Exhaust Gauge Pressure
Short Name: EGP
PID: 221445
Units: PSI
Max/Min: 30.0/0.0 (stock) 40.0/0.0 (performance and/or engine braking)
Equation: (((A*256)+B)*0.03625)-[221442]
It takes the Exhaust Back Pressure(PSI) and subtracts the device barometric pressure reading, giving you the backpressure above atmospheric pressure. Exhaust or boost leaks can make this reading very jumpy during WOT tests.

 

So after reading this other thread (https://www.ford-trucks.com/forums/index.php) and specifically Tugly's post #21, I am thinking that maybe I should check for an exhaust leak. Thoughts??

 

Is your device reading PSI or volts?

 

You are correct. MAP, Baro & EBPS should all be within a few tenths PSI of each other on a cold engine with the KOEO.

Have u tried plugging the old sensor into the harness just to see if you get the same or previous readings?

 

Not sure if device reads psi or volts. If I had to guess it would say psi since the PID reads exhaust back"pressure" but we all know what assuming does.

Unfortunately I have not tried replacing the old sensor to see my readings. Good idea. I will have to wait until I get home though since it is currently 2 states away.

I am going to visit Edge website to get more info on the PIDs. Is it possible that BAR, MAP, and EBP need to be calibrated?

 

I am seriously considering the purchase of an AE scan tool. Probably would make my life so much easier.

 

You could test it with a volt meter as well. All the scanner is doing is converting the volts to psi anyway.

They don't need to be calibrated.

Can you read your Baro sensor as well?

 

So in order to read the volts at the sensor, I am assuming that I just disconnect the plug and use the leads from the voltmeter to the prongs on the sensor, correct? What should it read? Amd I have no clue how to measure or read the BARO.

 

Subscribing. I'm in the exact same boat as you, Edge CTS, 0 EBP and 14 MAP, with EBP going to 5-6 under hard acceleration. Only difference is I'm trying to figure out why my boost is still low.