1995 GMC Safari 4.3L 4L60-E VIN W Code 83

Symptom = rough ide in park, terrible idle in gear. Very good engine performance as soon as it builds to about 2K RPM. Oil Pressure at idle is 30, 60 at 2K RPM.

Only Code 12 (of course) and 83 is thrown.

Would the bad TTC PWM Solenoid make the van run rough, or is their no relation between a bad idle and this solenoid??

Thanks, James