i did so with the brake...hissing continued...it's so fast though when it stops hissing it literally sounda like a house door being slammed shut.

 

Man, that sounds like the blend door in the heating and ac system. I have not heard of the door slam sound before with the ebpv.

 

neither have i...but that's got to be what it is; it's clearly out of the exhaust pipe. odd because i've never heard or or seen a probelm such as this before. the actual backpressure valve itself is underneith the turbo inside the pedestal..correct? and the connector for it is right in front when u climb into the engine compartment (meaning the valve and connector is facing the hpop and is built into the pedestal..right?) does this coem out with the hold down bracket removed or is there a c clip or something somewhere?!

 

Stand by, even though I am doing something else, I am going to look that situation up. May take a bit.

 

Exhaust Back Pressure Solenoid

****** content="Exhaust Back Pressure Solenoid" name="tps_proctitle"> Removal

1. Remove the turbocharger compressor manifold; for additional information, refer to Section 303-04D .

1. NOTE: The turbocharger is removed for clarity only.
   
   Remove the exhaust back pressure solenoid.
   1. Disconnect the electrical connector.
   1. Remove the bolt and the retaining bracket.
   1. Remove the exhaust back pressure solenoid.
   More to come. Could that have taken longer?

 

Backpressure Valve

Removal

1. Open the hood.

1. Remove the charge air cooler inlet and outlet ducts from the compressor manifold; for additional information, refer to Section 303-12 .

1. Disconnect the exhaust outlet pipe from the turbocharger.
   1. Loosen the clamp.
   1. Pull the exhaust pipe away from the exhaust back pressure valve.

1. Disconnect the exhaust back pressure valve.
   1. Slide the retaining clip toward the turbocharger housing.
   1. Disconnect the exhaust back pressure valve actuator rod from the exhaust back pressure valve.
   2. Remove the six bolts and the exhaust back pressure valve. Installation
   3. Follow the removal procedure in reverse order.
   4. NOTE: The butterfly valve should be fully closed when 4.5 kg (10 lb) of force is applied with the special tool.
      
      
      
      
      
      
      
      Using the Spring Gauge, adjust the actuator rod length to obtain the specified reading.
   I will get you the troubleshooting info in a little while.

 

Did you note the adjustment procedure at the end of the last post? I think you could use a quality fish scale for that.

 

Well, little there except to:



So without a live data monitor, you will be SOL. I would recheck my fittings on the tube and sensor. then check my actual valve and setting.

 

Mine has been hissing lately. Didn't pay it much attention. But it is loud b/c of my short dump exhaust. Doesn't cycle though, activates for a few minutes and stops.

 

Doesn't the PCM automatically cycle the valve when the engine is started, and the activate or disable due to IF- Then factors?

 

 

On most morning here on the central coast of Cali where overnight temps get down to low to mid 50's with daytime highs in the mid to upper 60's, my EBPV actuates almost every morning. Immediatley after start up all sounds normal then about 20 seconds later you can "hear" the valve beging to restrict exhaust flow and the pitch and tone of the exhaust changes to a "jet engine" like sound. There is not any increase in RPM during this time. Most mornings if I let it "warm up" until the valve opens it takes about 7-10 minutes of idle time. At this time the engine temp gauge has just started to register a temp indication. If I do not let it idle that long a quick "blip" of the throttle seems to bypass the EBPV operation and the exhaust sound returns to normal. Really, any change in idle like shifting out of Park and into Drive seems to deactivate the EBPV. I have noticed as the warm up process ends the valve seems to gradually deactivate and sounds a little like it is fluctuating back and forth at the very end of warm up. Maybe your temps are just not low enough for the valve to fully and completly actuate and hold?

 

Great explanation if how the EBPV works, even if you didn't really intend to....

Although, the idle speed did go up about 300rpm during warm-up when the EBPV closed. Then, any any action from the cab will deactivate and open the EBPV. Touch the brake or go pedal, or shift out of park(touch the brake), and it will deactivate. My neighbors surely loved the straight pipe 747 jet engine reverser hiss at 6am as I warm the truck up in -10*F heat.

I recently put in a new pedestal and removed the EBPV, so I had a hi-idle slot put on my recent DP chip burn. We shall see how it works come October.

 

At those temperatures, you'll most likely never see the engine warm up. Or at best three times as long as it used to take unless you drive it away, putting a load on the engine. It will be taking in air cold enough to carry off any heat generated.
My Dad used to live 30 miles from where he worked and drove a VW Diesel. The road was following a river canyon downstream most of the way.
He used to report to me that the car would warm up in the first ten miles going to the river canyon road and then the last 20 miles the temperature guage would go down and by the time he got to town the engine would be stone cold and rough and smoking like he had just started it. This would happen whenever the temperature would drop below zero.

 

Well, if I had to guess, I would say his valve is sticking, probably due to his linkage either binding or out of adjustment. That assumes of course that his sensor and tube are properly connected.