Something is wrong.

I can only get 18-20 lbs of boost(only in 5th and 6th) and I used to hit 32 with ease.

I thought I found the culprit when I found an area worn away on the drivers side intercooler boot. Put on a Piers heavy duty boot today. Still not fixed.

I used to run 5-10 lbs of boost down the highway. Now I have to find a good sized hill to get 10 lbs.

All my other intercooler boots seem to be in good shape. Took the vice grips to the fenders to make sure they don't rub on the boots. Tightened up all clamps.

I have the VanAaken 60 hp box with the boost elbow with the set screw. Checked to make sure the set screw was tight and everything was fine. I've heard people say they had to put a 1/8" NPT plug in the turbo and a bolt hose clamped on the hose to shut down the wastegate. Should I try this?

I have searched up and down and cannot find anything that looks lose or leaking.

Truck still runs allright and got 20 MPG going 80 MPH down the interstate, but the truck used to run a lot harder.

Also, will the truck not run over 20 lbs if my box died? Seems to run better then stock, but not sure if something might of happened?

 

you can check the exhaust side for leaks by pulliling the throttle lever foward and seeing if any smoke comes out any where. is it sputtering or shaking when it hits max boost, i had problems with my boost being low and it was a clogged fuel filter. what kind of fuel pressure are you getting

 

Fuel pressure gauge is out of commision as it started leaking. Trying braided line soon or saving for an electric gauge.

Fuel filter was changed 6500 miles ago. Maybe throw a new one in?

 

yeah mine only lasted about 7000miles. i was able to hit 50psi of boost, but after the filter was clogged i was only able to hit around 20-25psi. i would guess it's fuel related

 

I guess its possible.

It happened sometime while it was really cold. We were down to -20 F and a bunch of snow. Couldn't give the truck the onion for a while and then finally noticed I wasn't getting full boost.

 

Stock you shouldn't get any more than about 21lbs boost before defueling and setting code. Are you seeing excess smoke now more than before? Are your VanAaken box connections clean and greased with di-electric grease? Double check all intercooler boots for clamps being tight, as under load you can lose quite a bit of boost without noticing any wrong sealing of hoses.

Crimp off wastegate hose, or plug it off to see boost #'s while going for a twist. Then check for dirty/plugged fuel filter and change it if needed. Then you may have to pressurize system to find any pinholes in hoses, intercooler, or intake gasket leaks, if you still have low boost #'s.

 

might check the line to your gauge, a buddy of mine had a line get crimped, same symptoms, no real power changes, just didn't make any boost, & it was his line to the gauge, just a thought, Dusty

 

Changed fuel filter and unhooked gauge

No change

Will replace the line on my gauge here soon and see if thats the problem.