Test Description

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refers to the step numbers in the diagnostic procedures.

4 - When a Medium Resolution Resync occurs, an engine stumble should also occur. If the electrical connection of a component or an electrical wire is malfunctioning, an engine stumble or a medium resolution resync may be induced by wiggling the circuit or electrical connector.
5 - Operating malfunctioning, non-engine related electronic components may emit Electromagnetic Interference (EMI), which may cause a resync. This step determines if the medium resolution resyncs are being caused by an outside source.
6 - Thoroughly check any suspected circuitry. See DIAGNOSTIC AIDS .
8 - An intermittent problem may be caused by a number of conditions. See DIAGNOSTIC AIDS .
11 - Program the replacement PCM and perform the Crankshaft Position System Variation Learn Procedure. See POWERTRAIN CONTROL MODULE and CRANKSHAFT POSITION SENSOR under PROGRAMMING.