[jbdawson]

OTHER THOUGHTS: I'm not a mechanic so I really am guessing below:
This 3 lbs boost seems to be the key.
Could it be other exhaust valves not sealing.
Does this model turbo have a waste gate. I'm told no. If not then what controls the turbo speed and pressure? Maybe that is the problem.
I notice that sometimes when I have a lot of power, but not all the power, my transmission temp gauge is elevated. I have noticed the temp gauger is sometimes sporadic and often in the winter sits at 100 degrees.
Maybe Computers not talking. Local International shop seems to have a problem checking all 3 computers. What about installing a wiring harness for a single computer from a 3 computer system?
Lastly injectors? But what would they have to do with low boost.
Help please!

I'm no expert but here is a thought. On early 2000 model intl in line sixes there was a TSB regarding faulty variable vanes actuating mechanisms in the turbo. I was involved with a truck that intermittently would not pull the hat off your head. Diagnostics showed nothing and thee first trip to the dealer was useless. I communicated directly with intl who sent me a copy of the TBS and called the dealer and instructed them to replace the turbo without further ado. It worked. whether it goes back to 98 models I can't say and I would never find the TSB in a million years but there was a simple test that you could do visually that was indicative of the problem. It had to do with how far the actuator rod moved when the ignition was turned on. That's all I remember. Hope this is helpful.