Is there a good way to tell? I just put a T3 on my Jeep Wrangler a few days ago. It was making decent boost. About 5 psi at part throttle. I have never floored it because I am waiting on a wideband. Out of nowhere, the turbo is making zero boost. There are no leaks or smoke, and no boost. I checked the discharge piping and the BOV. Is this common when a turbo is junk, or could an internal engine problem cause a no boost situation. The engine seems to run normally.
I do still hear some spooling from the turbo, but nothing like when I first installed it. The turbo was also bought used on Ebay. I found the previous owner used a regular AN fitting on the oil feed with no restrictor.

Thanks,
Rob

 

Run the jeep until the turbo gets hot. Shot it off. Take off the filter and spin the wheel,

Report back.

 

I will warm it up tomorrow morning and check. I just spun it by hand while it is cold. The impellar spins freely, but I can feel it hanging up a little bit then spinning free again.

 

Your going to get expansion when it heats. If its hanging up there could be some particles in or around the bearing. Is this a journal bearing turbo? If there are metal particales around the bearing it can cause the turbo to lock up due to low oil flow around the bearings. I had a turbo with that exact problem. New bearings, sonic cleaning, and it was good to go.

 

This is the turbo I have. You might notice where the cheap Ebay oil feed line has a small kink right at the turbo. I wonder if I starved it and screwed the bearings up.
Could oil build-up in the compressor cause something like this? I have a line going from the valve cover right to the turbo inlet. I should put a seperator in the line I guess.

 

I doubt it. A running engine's pressure would probably squirt enough oil through that kink to keep the turbo alive, I'd imagine.

 

So even if an engine is in sad shape, the turbo should still make boost?

 

does your wastegate work correctly?! if it is open you will not produce boost...chek this before rebuilt....

 

I checked the wastegate. It is in the closed position.

 

see if it has shaft play. IF it doesnt have any id check for boost or exhaust leaks