Fuel pressure was tested when knock sensor was replaced and coils all look good. This thing had got me racking my brain. any other ideas?
ok, that is simple then. if you have tested fuel pressure and it's good. then this condition is due to a software issue in the pcm, recalibratation of the pcm is the fix. see the following bulletin addressing your concern.
BULLETIN NO.: 03-T-02
ISSUE DATE: January, 2003
CATEGORY TYPE: Engine-02
CATEGORY: Emission Controls
CORPORATION NO.: 03-06-05-001
SUBJECT:Engine Hesitation and/or Vehicle Lacks Power with DTC P0326 Knock Sensor System Performance Set (Install PCM Calibration)
MODELS AFFECTED:2000 - 2002 Saturn S-Series vehicles equipped with manual transaxies (MP2/MP3) built up to and including VIN 2Z258983 or automatic transaxles (MP6/MP7) built up to and including VIN 2Z263777.
CONDITION:Some customers may comment about the engine lacking power when accelerating and/or engine hesitation while driving.
CAUSE:This condition may be caused by the PCM misinterpreting normal engine noise/vibration as spark knock resulting in unnecessary ignition timing retard.
CORRECTION:To correct this condition continue with procedure in this bulletin