I have an 01 Cummins HO 6 speed and have the VanAaken box with the boost elbow.

Can not build boost like I used to. I used to get 32 lbs of boost with ease and now it struggles to get to 18 lbs.

If I remove the boost elbow and put in the regular fitting, I only get 10-12 lbs of boost.

Does the wastegate still just stay closed with the elbow? I am wondering if the diaphrams or springs are shot in the wastegate and it is opening even with the wastegate disabled via the boost elbow.

Or, does having the boost elbow in there render the wastegate worthless and that is not my problem.

I took an air compressor and pvc and put 10 lbs of air in there and could not come up with any leaks. Couldn't really get any more air in there with the pvc part blowing off. Replaced drivers side lower boot because I thought that was the problem, but it wasn't.

Brand new line to autometer gauge.

 

The boost elbow just minimizes the amount of "boost" that the wastegate sees. If you crank the boost elbow all the way closed then yes the wastegate is doing nothing. But if your problem is there with the stock fitting in as well you have a problem somewhere other than the boost elbow.

 

Thanks

But, that still doesn't answer my question.

My question is:

If the wastegate is shot, would the wastegate still open when its not supposed to with the boost elbow there?

 

I had a simular problem and found the waste gate arm was disconnected. you gotta get under the truck and look up at the bottom of the turbo to see it.
hope this helps
scotte

 

That depends if you have the boost elbow abjusted all the way closed. If the boost elbow is all the way closed the waste gate should be pretty inop. Or you could just unplug the waste gate and put a vac. cap over the nipple just for a test ride to see if it is still opening. If you unplug the waste gate from its boost source and cap the little nipple it will definately be inop unless its insides are shot.

 

"it will definately be inop unless its insides are shot"

That is the statement I'm looking for

If the insides are shot, then it might be my problem?

The boost elbow is adjusted all the way closed, so no air is getting it there.

But, it could still be the problem if the wastegate is shot, correct?

I looked under the truck and it is hooked up.

When I had 10 psi, it almost sounded like air was escaping from were the wastegate is hooked up in the exhaust housing part. Was hard to tell though. Could not hear or feel air escaping anywere else. Used soapy water and came up with nothing. Hose clamps have been tightened many times.

 

Sorry i couldn't help, Let us know what you find for others to learn from.

 

It doesn't matter if the wastegate actuator is shot, the gate will stay closed and you will get maximum boost. The gate has a rather strong spring that keeps it closed. I have never seen one fail in the open position but guess it could be possible.

 

Some year trucks had problems with the intercooler splitting. Does yours have plastic ends? Disconnect and plug the wastegate line, if you still get low boost, thats not the problem.
Very difficult to find boost leaks. I made a fitting to connect an air line to the intake, stuffed a rag in the turbo, duct taped it up, and turned the regulater down to 25 psi, and using a ball valve, so I could turn the pressure off and on, I pressurized it in my garage, (motor off of course). I found the AFC line was bad on mine.

 

Tried a different wastegate today. Its a PIA to install by the way.

Thats not the problem

Moving on. I guess unhook my box and see what that does. Make sure my box is working.

Then back to the drawing board with boost leaks.

 

Unhooked box

Even with the wastegate still blocked, only could spool 10-12 lbs. Box hooked back up, and back to 18 lbs. Definitely noticed quite a difference power wise. No smoke without the box hooked up too. Box hooked up and a little smoke. Same as when I had 32 lbs, or similar.

Tonight, I put about 15 lbs in and went from air intake in and then unhooked my boost gauge and went from intake manifold to turbo. Couldn't come up with any kind of leaks.

Also, what seals that piece right off the turbo, that is inbetween the turbo and the first rubber boot? Is there any gasket or anything? Its just metal on on metal it looks like, with one of the heavy duty clamps.

My next task is to take the first boot off and put a 3" PVC cap on that. Then crank up the air pressure to 20 lbs and see if it will hold pressure between the intake manifold and before the turbo.

 

Have you checked the intercooler for cracks?

 

I have looked pretty hard at it, but I have not removed it. That looks like a project.

Hopefully I will have a better idea when I can pressurize it without the turbo involved and crank the air pressure up to 20 or 25 lbs.

 

Please no comments from the haters here, but.....the dealer has a good tool to test the air charge system. I made one similar to it. The picts are in my gallery. I can adjust the regulator and test as high as 35 psi. I have a blow off valve that opens there as I do not want to test beyond that.

 

There is an oring @ the turbo elbow, i had to get one from the dealer less than $5.
Mine had gotten pinched and caused a leak.
You will see a groove that the oring sits in on the elbow, don't try RTV it doesn't work.