Diagnostic Aids
WARNING: This page is about a different car, the 2003 Pontiac Montana, 2003 Oldsmobile Silhouette, and 2003 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
Ensure the wiring harness is not stretched too tightly or other components are pressing on the A/T inline 20-way connector body. Also inspect for proper clearance to any other components and wiring. Refer to INTERMITTENTS in Trouble Shooting - No Codes in Engine Performance.