Exhaust Backpressure Valve/Tube?

[dieseldirt]

Having some issues with the '97 PSD in my signature... It has been starting and running ok, not sure if it's just the cold weather or what.

New to the PSD, I have done a lot of reading about the EBPV and still don't really get it. I have read that you don't really need the EBPV? Local shop just calls it an Exhaust Backpressure Tube and said that mine is rotted and that it would run better if I replaced it. Been putting off digging into it myself. The truck came from Boston, and the exhaust is very rusty from the manifolds on out.

Since colder weather hit, it's been acting up until it gets warmed up. I was driving today, before it was fully warmed up, it would momentarily loose power and make a loud nasty jake brake noise on deceleration (this truck does not have a jake brake) and it was even louder if I pushed the "overdrive off" button... It didn't really want to knock out of gear to idle while driving... It would idle fine just sitting... Of course this is my first winter with an E4OD and it is a "newer" reman E4OD... I figure when one thing is out of whack with the computer, everything else gets screwy too, so can be hard to find the true problem(s)...

It has been making the nasty noise with momentary power loss all summer just after startup and that's it... never while driving. Shop said it was the serp. tensioner rubbing on a pulley and that they fixed it.

Once I get everything warmed up, it drives fine with no complaints...............OD Button/TC Lockup works with no nasty noise either.........

 

[79jasper]

That would be the ebpv. It's sorta like a heat riser on Gasser's.

When first started it cycles once to make sure all's well.
When it's cold out, it'll come on a lot until the engine is warmed up.

You could replace the tube and sensor. (At least tube) Should fix it from coming on too much.

Or you can just unplug it.
You'll run fine without it, and save fuel.

Look for a 2 wire plug under the turbo compressor.

 

[OLDBULL8]

The EBPS senses the exhaust back pressure, that in turn closes the EBPV which closes the exhaust partially to warm up the engine quicker. That tube is easy to replace or clean out, so is the sensor, but have to be careful, it has a diaphram in it that can be punctured.

http://www.dieselorings.com/1994-1998-ford-7-3l/sensors-and-backpressure-tubes-parts.html

This refers to 2002 but your EBPS is the same location. Lots of other info there on his maintenance page.

http://www.guzzle7pt3.com/ebps.php

 

[lindstromjd]

Everyone else pretty much hit it here, but just so you are 100%...

The EBPV (exhaust back pressure valve) resides in the back of your turbo. It is a flap that closes to force the engine to work harder to push out exhaust, thus warming it up faster. That is the thing that can be unplugged. It can also be "deleted" by taking your turbo apart, but it's easier to just unplug the wiring that activates it. The exhaust pressure tube is in the front of the engine coming off the passenger side exhaust manifold and has a sensor in it right up next to your HPOP reservoir. That tube needs cleaned out, and that sensor needs to be kept plugged in.

 

[dieseldirt]

Thanks a lot everyone. It all makes sense now that I know there is a valve, sensor and tube.

Can the valve ever go bad and block the exhaust randomly/too much, or are the problems always related to the sensor and/or tube?

I unplugged (for now) the connector underneath the turbo intake, and it seems to be running better. My EBP Tube is broke off 2 inches below the Sensor. So this means I have another exhaust leak to add to the list....... How much leaking is too much? It now has OK power and drivability, but sounds like crud when I hammer down on it.

 

[79jasper]

You definitely need to replace the tube. The sensor controls more than just the valve.
Yes they can stick closed.

Sent from my USCC-C6721 using Tapatalk

 

[dieseldirt]

Thanks.

OK I will order a tube.. Anyone know a source for the OBS one? I think that one on Guzzle's store was for 99+.

Is it gonna probably come apart nasty on the manifold end? I guess I can't make the tube leak worse that it already is.

What all does the sensor do? And how would I know if the valve was sticking/stuck?

 

[OLDBULL8]

Thanks.

OK I will order a tube.. Anyone know a source for the OBS one? I think that one on Guzzle's store was for 99+.

Is it gonna probably come apart nasty on the manifold end? I guess I can't make the tube leak worse that it already is.

What all does the sensor do? And how would I know if the valve was sticking/stuck?

This stainless steel tube runs between the passenger's exhaust manifod and the EBP Sensor mounted on the front of the HPOP reservour. WIth age the tube will plug with soot and can rust or break apart. The EBP sensor system feeds data to the PCM which effects many of the fueling tables within the PCM and should be kept in good working order to acheive your best fuel economy.

The fitting on the exhaust manifold is usually OK. No big deal to replace the tube.
I'm sure Guzzle has your tube, just call them. You can bet a dealership cost will be a lot higher.

 

[rthomas]

I wired mine to a toggle, it works when I want it also doubles as an exhaust brake and can be used to smoke the **** out of tailgaters.

 

[dieseldirt]

I wired mine to a toggle, it works when I want it also doubles as an exhaust brake and can be used to smoke the **** out of tailgaters.

Neat.. My EBPV was working like an exhaust brake when it was malfunctioning, I just unplugged the harness, glad it's now stuck open and not closed...

How would you hook it up to a toggle switch? IIRC there are 2 or 3 wires.

 

[dieseldirt]

I did get my new tube installed after weeks of soaking the bottom fitting with PB Blaster, the old one (what was left of it) came apart surprisingly easy. Installed the new tube with plenty of anti-seize.

 

[79jasper]

There's two wires.

IIRC, I used guzzles or baz's write up.

 

[dieseldirt]

So you wired your EBPV to a toggle switch to warm up your truck faster in the winter while parked, or to use like an exhaust brake while rolling? Or both?

I read that using the EBPV like an exhaust brake may harm your engine?? Or blow out some oil seals or something?

 

[79jasper]

I used mine as a brake.
It automatically kicks in to warm up the engine. That's why it's there.

Unless hauling heavy, it's really not worth doing. Personally I'm going to delete mine when I pull the turbo to replace my ate up impeller.

 

[dieseldirt]

I used mine as a brake.
It automatically kicks in to warm up the engine. That's why it's there.

Unless hauling heavy, it's really not worth doing. Personally I'm going to delete mine when I pull the turbo to replace my ate up impeller.

Yep it is automatic if you have it connected

I am definitely hauling heavy enough, in the mountains, and love the idea of a "free" exhaust brake to help control my speed, but I don't want to mess up my engine in the process... All I know is the EBPV works different than a true aftermarket exhaust brake and there are guys saying it will mess something up to use it as a brake, even though it "sounds" and feels similar........