Hi,
What guitar is this? What are the pickups? What did you replace them with? Is it both pickups that are anemic?
I would check the wiring and reflow the solder joints. If that does not show obvious errors or cure it, then it's time to thoroughly check each component, e.g. desolder the tone and volume pots and wire the bridge pickup directly to the jack. Still anemic? If no, add the volume control. If this makes it anemic, replace the volume control. Do the same with the tone control. If the tone is still anemic with the pickup wired to the jack directly, then the pickup is not right for that guitar, your playing style or rig.
Repeat the procedure with the neck pickup.
Good luck
Stephan
