I was wondering about the MAP and BARO as well, I am wondering if they are not reading in in/hg, one atmosphere in inches of mercury is 29.92" at sea level or 14.7PSI, which makes me also wonder if the EBP is reading PSI.

 

Hey, that makes sense. I haven't played with my DashBoss for a while. I don't remember in/hg being the default value. I can't hook mine up and check it right now, maybe someone else can verify?

EBP is behaving badly either way though. And MAP is up way high at 2,500rpm.

 

2004/05 Emissions and EBP Sensor Recall 05E15:
Certain 2004 and 2005 trucks are being recalled for computer reprogramming and replacment of the Exhaust BackPressure sensor and, in some cases, the EBP sensor connector. Econolines built between 12-9-03 through 5-28-04, and SuperDuties and Excursions built between 12-1-03 through 5-31-04 will have the EBP sensor connector replaced. SuperDuties and Excursions built between 9-29-03 through 11-30-03, or between 6-1-04 through 1-18-05, and Econolines built from 6-1-04 through 3-3-05 do not have the connector replaced. All of the above trucks will be reprogrammed to the latest calibration level. Since many trucks ahave already had the EBP sensor replaced with the current level part, the sensor part number should be inspected. If the part number on the sensor is 1850353 over a number starting with "C1", the sensor does not need to be replaced. Any other numbers, or unreadable numbers, will be replaced.

2003-05 Various Running Problems, Check Engine Light; New EBP Sensor:
Trucks built before 1-17-05 that exhibit buck/jerk, hesitation, lack of power, stalling, stumble, black smoke, surging, rolling idle, changes in engine sound at idle or when driving at a steady speed, or with the trouble codes P2263 or P0299, may have an exhaust backpressure sensor signal that is incorrect or erratic. A revised EBP sensor is available if this is found to be the case. Part number 4C3Z-9J460-A. Broadcast Message 3815.
Normal EBP signal reading should reflect atmospheric pressure with the key on/ engine off. Typically, this is 14.7 PSI/0.88-0.9 volts at sea level, decreasing one PSI/0.10 volt for every 2000 feet of elevation. It should be within 0.5 PSI of BARO and MAP sensor pressure signals.

ICP/EBP Sensor Repair Kit:
Both PowerStroke engines may exhibit codes related to the ICP(7.3: P1280; 6.0: P2285) and/or EBP sensors (P0472). If these codes are present, clear them. Start the engine and wiggle the sensor connector that matches the stored code. If the code returns, replace the sensr connector--P/N 3C3Z-12224-BA for 94-96; 3C3Z-12224-AA for 97-2004. Broadcast Message 1078/SSM #17573.

 

He gutted the cat Rusty so the exhaust should be fine.

 

Wow that's a ton of info thanks guys, yes the cat is empty it's just a shell to get through emissions. I wasn't sure wich Baro to choose. I used absolute press instead of the guage press option. I think there was a different MAP option as well. I can't look unless it's connected to the truck so I'll have to give it a look again tonight. As for the recalls I'm going to have to give my Dealership a call. Mine fits in the categories for some of them. Actually the bucking and hesitation part is exactly the symptom I had last year and could never figure it out. Thanks again guys I'll let you know what I find.

 

So I took apart my EBP tube and it was clear. I couldn't remove it completely because it's to rusted on the exhaust manifold. I did get a wire down it to clean it out a little and there wasn't to much junk on it. I then removed the sensor and it was packed full of crud. I cleaned it out good but there looks to be a diaphragm inside that I could of damaged. I then cleaned out the elbow it thread into and put it back together. I took it for a ride and it wasn't much better. Can the EBP sensors be cleaned or should I just get a new one.

 

Completely clogged





This is at idle, I have the EBP set to read gauge pressure not absolute





As you can see my boost keeps dropping off





And my MAP seems to be following the boost which would make sense right?

 

I'm guessing your map sensor is gone and as soon as the pcm senses boost above 28 psi, it goes to limp mode .... forcing the boost back down. MAP - ATM = boost.

 

Ok so I replaced the MAP sensors today. Did absolutely nothing, reads exactly the same. I even tried unplugging my EBP sensor and still nothing. Still no codes, somebody mentioned it being in Limp Mode today. How would I know and what else can I check. I'm thinking about pulling the EBP sensor again tomorrow to see if any gunk from the tube made it's way up there and even the EGR to make sure it's not stuck open. Besides that I'm stumped. Not sure if I should drop the money on a EBP sensor, if I do I geuss that will at least eliminate that from the problem.

 

One thing you can do is remove the butterfly valve from the EGR throttle body, if this is malfunctioning it can cause boost issues as the MAP sensor is after this valve. The EGR throttle body is what controls the flow of air into the intake manifold from the charge air cooler (CAC), just unbolt the throttle body and remove the plate from the shaft that it is mounted on inside the throttle body and reinstall the throttle body.
I think your MAP and BARO are fine as they are reading in inches of mercury which is 29.92" at sea level or 14.7 PSI, now that EBP sensor looked pretty bad.

 

Either the MAP is doing strange things, you've got a small tear in one of the cac tubes or connections that opens when the boost goes up, then closes quickly and brings back your boost, or your turbo veins are doing strange things.

Judging by how quickly your boost falls off and builds back again, I don't suspect the turbo veins. I don't think they can react that quickly.

Did you check the MAP tube for plugging and cracks and leaks before replacing the MAP sensor?

Check all the cac connections and tubes for leaks. The loss, and building back, of boost leads me toward the MAP tube and it's connections.

 

You know it didn't even cross my mind to check the tube when I replaced the MAP sensor, I was in a hurry and in the rain. I'll have to check that out, I just ordered a new EBP sensor off ebay so I'll throw that in also. It's so weird watching the boost build and then dropping to 0 psi, yesterday I was getting on the highway and held it to the floor and the truck didn't respond at all until at least a good 10-15 seconds later. Didn't blow any smoke or anything. I'm definately going to check everything you all as soon as I can, And I'll post back. I just want this fixed. Thanks Guys!

 

Ok so I finally got my EBP sensor in the mail. I pulled the old one and started the truck to make sure the tube was clear and it was. I installed the new EBP sensor, Made sure the MAP tube was clear, removed the butterfly valve from the throttle body, and pulled the EGR to make sure it wasn't stuck open. Truck ran exactly the same. Now what? I did notice oil on my boots, I doubt it's a boot or cracked tube because it's going to 0 psi of boost. What would cause it to go to 0 boost? I'm using a DashBoss so I heard I'm reading the boost it's commanding not the boost it's actually making. So if that's true what would make it command 0 psi of boost. Oh and still no codes.

 

Either there is a quirk going on with dash boss or there is an electrical grilling causing your sensors to read sporadically.

Ive never heard of reading the commanded boost. Map-baro=boost. It's pretty simple. Your map and your boost are following.

It's getting close to time to pull the turbo and check the veins.

 

I read online about a VGT relearn, I figured what the heck it can't hurt and I'll try anything that's easy and free. So I did it. I programmed my truck back to stock, disconnected batteries, crossed the cables and turned on headlights for 10mins, reconnected batteries and took it for a rip. I can't even believe it actually worked! Pulls like crazy once again! Only thing is my tranny is also relearning now, which means it shifts like **** , I up shifts way to fast. I know it will take a while for it to get back to normal and I'm ok with that. Should I run the stock tune though while it's still trying to learn? I retuned it win my SCT with my Innovative tunes but I'm not sure if I should take it out until the tranny finds it's happy place. Any thoughts, thanks for all of your input also I learned a lot more about my truck. Oh also when I hammer the throttle my boost still drops to 0 psi while the truck pulls like crazy so I think my DashBoss is screwed. Thanks again guys!