Bypass the boost control solenoid, it is activated when the knock sensor detects pinging.
I have replaced my knock sensor and done the knock sensor bypass (resistor mod) and bypassing the solenoid is the only long term solution.
I have 2002 SE SC and have owned it from new.
2 years into bypassing the solenoid and installing a smaller pulley and everything is fine.
11 PSI Boost
Always use 92 octane.