Those of you who have had a stuck turbo, and can now only boost to 21-22 psi, check your intercooler for cracks. Mine would only boost to 21 and had a code for turbo underboost. I could watch the boost go to about 22, then drop to 21 and hold steady. My intercooler is cracked along the left lower corner, bottom three vanes and a long crack along the metal portion of the end cap for about 8 inches. It looks to seal up for the most part, until it would hit 22 psi, then the crack would open up.

I found the leaks by filling the cooler with water while it was out. I capped on end and filled the other with a garden hose. When it reached the top, I sealed one end with the intercooler boost and a pvc cap, the other with a pvc cap fitted with a schrader valve clamped into the boot. I then pressurized the cooler with approximately 22 psi and watched the water come out of all of the cracks.

Dammit.

 

Good catch. I've been having issues (not low boost) so I got on it hard today and got 27.3lbs of boost!!

 

I have not seen that very often just a few times in 10 years of working on 6.0but it does happen. I have occasionally got superglue to work on the plastic tank but it needs to cure for a couple of days before useing it.

 

This one is cracked in the aluminum area on the back side of the plastic cap. I wish it were the plastic end cap, I'd plastic weld it.

 

If you can get to it, maybe try JB Weld or the putty version -- I've been pretty amazed at some things it has saved for me...

On edit: that'd be for the metal -- haven't had any luck with it on plastics, but there are some good plastic cements out there...

 

Jf accessible it could be mig welded.