My first drive to work on a new set of tunes had a cloud over the event. My first warning sign was the surprise level of the fuel gauge... but hey, I've been burning a ton of fuel in idle while testing/troubleshooting. Reset the lie-o-meter and I see a scary4-5 MPG drop from before. It's too soon to tell, but I'm nervous. After work, I've got the truck warming up while I walk around the truck to look and listen... and I see this for the first time:



Many of you may say "I don't see anything", but my truck is very white, it was just washed, I have 65 miles on a new tuner, and that's soot behind the tailpipe. I hadn't seen that since the exhaust leaks were fixed 16 months ago.

BUT! I already know I have an issue with the truck, so I push the speed dial to the stealership and tell them I need an EBP sensor for a 2000 F250 7.3L. The reply on the phone was "Oh, hi Rich. I almost didn't recognize you because you're on the speakerphone." Now that's just pathetic... this tells me I no longer have a life. My wife gets complimentary rooms at the casino, and I get free coffee at the dealership.

My EBP sensor was reading about 17 PSI with the engine off. If you get bored and want to see something interesting (well... this geek thinks it's interesting), search the web for "absolute air pressure" and "altitude". What you will find is 17 PSI of air pressure is a pretty low altitude. The correct reading for where I live is 14.2 PSI. If the MAP, the BARO, and the EBP don't all agree my absoulte pressure is 14.2 PSI, then the tuning can't compensate and all kinds of annoying things can happen. One symptom is poor fuel economy... I'm guessing because it messes with the fuel applied, but I'm not a tuner guy.

Anyway, 3 PSI above normal is significant. I get a 3 PSI rise in EBP at 50 MPH, so the tune might behave as though I'm going 50 MPH... while in the driveway. I get the new EBP sensor, pop it in with my shiny new 1" deep socket (fired off a Buck$Zooka round at Sears to get Stinky tools)... and yes, I countered with a 5/8" wrench on the fitting under it. I get readings of 14.2 PSI on all sensors. Life is complete once again. Test drive today.

 

That is just to funny,I feel ya..My local dealer not only knows my name but sells me at 10% above cost and delivers to my office..Good luck on the cloud

 

Man, I need to get an AE. Guess mine is okay for now, my tip ends a few inches short of yours, and the white is clean,but I know where to look if.
Thanks.

 

See Rich, thats the difference between the way I descibe things and the way you do. I would have called it Stinkys sh%t stain.

 

People would probably feel more compelled to click it.

For those who are curious what your PSI should be on your MAP, BARO, and EBP: [LINK]

 

What is an AE. it sounds like a cool toy where can I get one.

 

Check out Riffraff site. Auto Enginuity? It's diagnostic software you use with your laptop.

 

So Rich - If all is right with these sensors, & I take a trip to the top of Pikes Peak - they will automatically sense the change in pressure & adjust tuning accordingly - weather tuned or stock truck , eh ?

 

now that your ebps is reading right...
have you tried the other chip again?

 

That's correct. These sensors aren't just for passing emission tests (well... not only), they are used to determine when and how much fuel the engine gets to optimise efficiency and power without smoking or burning up the place, and to warm up the truck faster when cold. A tuning guy knows more than I do on this, but I can tell you my fuel economy has already bounced back since I swapped the EBP sensor, and I found some new power under the hood with these tunes and a repaired truck.

The EBP sensor was a recent failure. I check that stuff and I caught it as soon as it happened. It would be pretty silly for me jump up and down about that last signature link like a kangaroo on a trampoline and not click it myself. Go back? Uh... I don't think so. I still have noisy injectors though, that's the higher priority.

 

you did the ac code sticks right?

single shots are noisy...
just the nature of the beast...
if noise is your only complaint now... maybe add some dynamat?

or do you hear something that sounds problematic?

 

You personally heard the one. I now have another one doing the same thing, plus I have one "clicking". They gotta go.

It's only been one day, but it's not too early to post some results. I caught the EBP sensor when it was real bad, but I think it's been fading a while.

Early symptoms:

• Lugging at 1400-1600 under light load (empty on a hill)
• MPG drifting down (masked by winter for me)

Late symptoms:

• Lackluster performance
• Profound loss of MPG
• Vibration, like knobby tires.
• Lugging about the same
• Soot behind tailpipe

 

Well, I've been meaning to clean my EBP sensor and tube since I bought the truck, guess I could tackle that this evening. Correct me if I'm wrong, but your sensor was reading HIGHER pressure than it should, resulting in MORE fuel being burned than necessary. A clogged tube or sensor would result in LOWER pressure reading, causing rough idle and lack of fuel (which means lean mixture, more throttle, lower economy???). I can't check what it's seeing because I don't have AE yet.

 

I think it's more complex than that. It's just my guess, but I think the MAP has more impact on the fuel mix and the EBP is a measure of load. If the PCM thinks the load is heavier, it will then whack out the whole thing... I'm guessing timing gets an unnecessary (or unhealthy) adjustment. The shifts will definitly be impacted... rough/squishy... earlier/later... something.

Higher reading, yes. A clogged EBP sensor can have crud wedged against the diaphram, giving a high reading as well. I don't think exhaust is supposed to flow there, just dead-end... but I'm not the expert on that.

 

That's my understanding as well. I know the tube rusting out causes issues, and "coal" can get stuck. I assumed blocking the pressure, but you're right, it could press against the diaphragm causing high readings as well.