Older Tajima Neo - tension issues causing false thread breaks.

Hi there, I'm currently working with a 2003 Tajima NEO; since it is an older model, there aren't any techs in my area willing to look at it, so I'm fumbling around as my own tech. The current problem is that on a few of my needles, the thread tension ramps up past 150 once it passes through the uptake lever, causing the uptake spring to stick up and the machine to return a false thread break error. Thus far I have tried:

• Different pattern
• Different color thread on the needle
• Replace needles
• Replace thread uptake spring
• Clean and check thread guides on uptake lever for damage/wear
• Clean, oil, and check thread uptake lever for damage/sticking
• Adjust upper tension
• Wrap the thread a second time around the tension disc
• Replace tension disc
• Check presser foot for damage

Some of it was done in the name of diagnosing just where the tension change was, but I'm out of ideas. Has anyone else had this issue? Thanks in advance for any responses.