Engine Cranks Slowly

WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Perform the following checks:

Battery - Battery Inspection/Test. Refer to Battery Inspection/Test (Non-HP2) in this section.
Wiring - Inspect the wiring for damage. Inspect all connections to the starter motor, solenoid, battery, and all ground connections. Refer to CIRCUIT TESTING , WIRING REPAIRS , TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems.
Engine - Make sure the engine is not seized.

If the battery, the wiring and the engine are functioning properly and the engine continues to crank slowly, replace the starter motor. Refer to Starter Motor Replacement (4.2L Engine) in this section.