I have the Joe P manual boost controller and for some reason I can either only boost 10 psi or 1-2 psi. Nothing in between. I took it apart to look at the inside and I notice two ball bearings on both ends of the spring. But nothing else seems to be wrong. Anyone know how I can fix this damn thing?

Not really sure but you might have a bad spring. The spring might look fine, but it's possible that certain areas on the spring could be stiffer/softer. Just a thought.